MANUAL 


HYDRAULIC    MINING. 


FOR    THE    USE   Of 


THE    PRACTICAL 


T.  F.  VAX  WAGENEN,  E.M. 


THIRD  EDITION  DEVISED. 


NEW  YORK: 
D.    VAN    NOSTRAND    COMPANY, 

23  MURRAY  &  27  WARREN  STS. 
1900. 


Copyright, 

D.  VAN  NOSTRAND  CO., 
1897. 


PREFACE. 


THE  following  pages  are  written  solely  for 
the  use  of  the  practical  and  working  miner, 
who,  while  rarely  deficient  in  common  sense, 
is  generally  unacquainted  with  the  principles  of 
physics  and  more  or  less  rusty  in  arithmetical 
methods.  In  the  daily  discharge  of  his  business 
he  is  continually  confronted  with  engineering 
problems  of  more  or  less  complexity,  and  com- 
pelled to  depend  for  their  solution — trained  en- 
gineering advice  being  unobtainable  or  too  ex- 
pensive— upon  his  own  limited  experience  or 
upon  that  of  his  co-laborers. 

Under  these  circumstances,  errors  in  con- 
struction and  operation  are  frequently  repeated. 
The  author  ventures  the  hope  that  the  study  and 
use  of  the  following  pages  will,  to  some  extent 
at  least,  obviate  the  necessity  for  costly  experi- 
menting, now  so  common. 

3 

438587 


The  Manual  does  not  claim  to  cover  the  whole 
subject,  nor  to  answer  all  questions  in  hydraulic 
engineering.  Nor  will  it  take  the  place  of  an 
experienced  and  competent  engineer  in  impor- 
tant enterprises.  On  the  contrary,  no  miner 
who  is  not  himself  an  expert,  and  who  can  af- 
ford it,  should  be  without  such  advice  and  assis- 
tance as  can  be  afforded  by  a  well-educated 
and  practised  hydraulic  engineer. 

THEO.  R  VAN  WAGENEN, 


CONTENTS. 


PAGE. 

INTRODUCTORY  REMARKS,          .  .  .7 

CHAPTER  I. 

GENERAL  PHYSICAL  CONDITIONS,  .  e  .11 

CHAPTER  II. 
GENERAL  METHODS  OF  PLACER-MINING,          .  .     19 

CHAPTER  III. 
DIRECTIONS  FOR  THE  MINER,     .  .  .  .25 

CHAPTER  IV. 
THE  PROPERTIES  OF  WATER,    .  .  „  .43 

CHAPTER  V. 
CONSTRUCTION  OF  WATER  WAYS,          .  .  .51 

CHAPTER  VI. 
FLOW  OF  WATER  IN  FLUMES  AND  DITCHES,    .  .     58 

CHAPTER  VII. 
IRON  PIPING,      .  .  .  .  .  .04 

CHAPTER  VIII. 
NOZZLES  AND  DISCHARGE,          .  .  .  .79 

CHAPTER  IX. 

THE  SLUICE,       .  .  .  .  .  .82 


INTRODUCTORY  REMARKS. 


HYDRAULIC  mining  is  the  art  of  separat- 
ing gold  from  gravel,  sand,  and  clay  cement, 
through  the  medium  of  moving  water  and  the 
force  of  gravity. 

The  process  is  one  lying  wholly  within  the  do- 
main of  the  science  of  mechanics — a  branch  of 
human  knowledge  now  so  well  understood  that 
results  may  be  predicated  with  extreme  accura- 
cy, if  correct  premises  are  obtained. 

•Hence", ^hydraulic  mining  presents  fewer  risks 
and  more  certainties  than  any  other  department 
of  mining,  other  tilings  being  equal.  It  is  sim- 
ply a  question  of  moving  gravel  or  soil  from  one 
place  to  another.  Given,  therefore,  in  addition 
to  an  abundance  of  water  to  move  and  wash  the 
gravel,  ample  space  to  deposit  it  again  after  it 
lias  been  washed,  and  the  problem  of  obtaining 
a  profit  is  reduced  to  a  minimum. 


8  INTRODUCTORY  REMARKS. 

Gold  occurs  in  gravel  deposits  in  a  metallic 
condition.  The  chemical  and  mechanical  ope- 
rations required  to  separate  it  from  the  vein 
substances  with  which  it  was  originally  asso- 
ciated have  all  been  performed  by  nature.  That 
wonderful  agency  has  also  supplemented  her 
work  by  again  collecting  the  particles  of  metal 
^wifckifi  certain  limits,  fir-other  words,^  cfegrada- 
tion  and  erosion  of  quartz-veins  has  been  fol- 
lowed by  the  partial  concentration  of  the  mfc 
apt 90* broken  up;  and  while  this  operation  has 

^rr^*^i 

not  resulted  in  Jwr  enrichment  of  the  gold-bear- 
ing material  ifm^-the  contrary,  it  is  much  poorer, 
-%nik "for  bulk);  the  metal  is  placed  in  association 
with  substances  from  which  it  uiagrbe  separated 

e\l 

with  extreme  ease  and  very  small  cost. 

A 

As  an  example,  the  gold-bearing  veins  of  the 
western  United  States  have  an  average  value  of 
about  ten  dollars  per  ton  of  quartz  extracted, 
which  ten  dollars  can  be  mined,  transported  to 
mill,  crushed,  amalgamated,  refined,  and  sold  at 
a  gross  cost  of  about  eight  dollars  per  ton,  or 
eighty  per  cent.  The  same  gold  vein,  after  pass- 
ing through  the  laboratory  of  nature,  will  consist 


IN  TROD  UCTOR  Y  REMA  RKS.  Q 

of  a  gravel-bed  or  deposit  worth  about  twenty 
cents  per  ton,  which  twenty  cents  may  be  se- 
cured and  marketed  at  a  cost  not  over  five  cents, 
or  twenty-five  per  cent.  Other  things  being 
equal,  therefore,  hydraulic  mining  presents  three 
times  the  chance  for  profit  that  is  fountl  in 
gold  quartz-mining,  and  one-third  the  riskpivith 
the  additional  advantage  that  the  extent  and 
richness  of  ^k^'  gravel-beds  may  be  completely 
studied  and  ascertained  before  working  Ht,  and 
at  a  slight  cost  ;  while  vein-mining  is  from 
first  to  last  more  or  less  of  an  experiment  and 
'4  chance.  \*f) 

The  records  of  mining  show  that  over  seventy- 
five  per  cent,  of  all  the  gold  mined  within  his- 
toric times  has  been  derived  from  the  working 
of  gravel-beds.  It  is  also  a  matter  of  fact  that 
the  area  of  auriferous  gravel  deposits  is  vastly 
greater  than  that  of  quartz-veins.  This  is  es- 
pecially the  case  on  the  Pacific  coast  of  both 
North  and  South  America.  The  immense  chain 
of  mountains  extending  from  Alaska  to  Pata- 
gonia bears  evidence  of  having  been  at  once  one 
of  the  loftiest  and  oldest  of  the  great  upheavals 


I O  IN  TROD  UCTOR  Y  REMA  RKS. 

of  geological  time.  From  one  extremity  to  the 
other  it  is  ribbed  with  metallic  veins,  which 
through  the  ages  have  been  worn  down  and 
away,  and  their  debris  deposited  by  rivers  and: 
i^ses- and  glaciers,  in  all  the  various  ways  in 
which  nature  works.  And  these  great  deposits, 
consisting  of  old  channel-beds,  forsaken  bars, 
grass  and  forest  covered  moraines,  and  sterile 
terraces,  contain,  beyond  a  doubt,  more  millions 
than  have  yet  been  mined.  The  great  Bine  Lead 
of  California,  which  has  been  traced  for  seven 
hundred  miles  along  the  western  flank  of  the  Si- 
erras ;  the  channels  and  bars  of  Montana,  which 

7&?v/"C-^L 

represent  the  pathway  of  the  Missoun^of  old; 

the  great  morainal  deposits  of  Western-  Colorado; 

/i 
ated  the  arid  and  dry  terraces   and  ravines  of 

A 
Arizona— all  these  are  nature's  gold-filled  vaults, 

inviting  the  enterprise,  the  energy,  and  the  in- 
genuity of  tfee=3pfe*fee  man,  and  promising,  not 
the  irregular  and  doubtful  returns  which  charac- 
terize precious-metal  mining  of  the  present  day, 
but  steady  and  continuous  results,  based  on  an 
imkustry -as  legitimate  and  safe  as  agriculture  or 
general  trade. 

© 


CHAPTER  I. 

GENERAL  PHYSICAL  CONDITIONS. 


GKAVEL  deposits  containing  gold  are  gene- 
rally considered  to  be  the  disintegrated  remains 
of  mountains  which  were  originally  seamed  with 
auriferous  quartz-veins,  or  of  strata  of  rock  in 
which  the  metal  was  disseminated,  or  both. 
The  material  forming  these  deposits  consists  of 
gravel,  rounded  boulders,  sand,  and  clay,  gene- 
rally being  in  .conformable  layers  or  strata,  b.ut 
at  times  disposed  without  regularity.  These  de- 
posits are  beyond  doubt  the  result  of  mechanical 
precipitation.  The  occurrence  of  gold  dissemi- 
nated through  the  gravel  is  generally  ascribed  to 
the  same  cause,  though  some  are  inclined  to  be- 
lieve that  chemical  action  has  supervened  in  the 
case  of  the  metal.  The  point  is  one  of  more 
scientific  than  practical  interest,  though  the  lat- 


I  2  fft  DRA  ULIC  MINING. 

ter  theory  will  perhaps  explain  why  placer  gold 
is  purer  than  vein  gold. 

Gravel  deposits  may  be  subdivided  as  follows  : 

{a)  Ancient  river-channels. 

(£)  Recent        "  " 

(6-)    Bars. 

(d)  Moraines. 

(e)  Terraces. 

(/)  Lake-bottoms  (ancient  and  recent). 

In  general  it  may  be  stated  that  gold  will  be 
found  in  greater  quantities  and  in  coarser  frag- 
ments in  deposits  which  are — 

1.  Nearest  to  the  original  deposits. 

2.  Have  been  deposited  on  the  steepest  grades. 

3.  Contain  the  most  gravel  and  boulders. 

4.  Contain  the  most  iron. 

There  are  many  cases  in  America,  however, 
where  the  gold  is  found  almost  exclusively  in  the 
clay  or  cement  layers,  but  this  does  not  appear 
to  be  the  rule. 

Where  gravel  deposits  are  made  up  of  several 
layers  of  differently-sized  material,  often  some  of 
these  layers  are  wholly  barren,  or  at  least  un- 
profitable. In  general  the  metal  is  found  in 


HYDRA  ULIC  MINING.  I  3 

greater  quantities  in  the  lower  layers  of  the  gra- 
vel, near  and  on  the  bed-rock. 

Frequently  in  exploring  and  testing  gravel  de- 
posits it  is  necessary  or  convenient  to  find  the 
weight  of  the  mass  ;  this  operation  will  be  facili- 
tated by  the  following  table  : 


One  cubic  ft.  of  dry,  loose  loam  weighs 72  to    80  Ibs. 

packed  "          "     90  to  100  " 

"          "  wet,  loose      "          "     66  to    68  " 

"  "     packed'4          "     85  to    95  " 

"          "  solid  quartz  "     165  " 

"  broken    "  "     94  " 

solid  limestone         "     ....170  " 

"          "  broken     "  "     96  " 

"          "  fine  sand,  dry,         "     100  to  117  " 

ordinary  gravel,  free  from 
cement,  and  containing  no  heavy  boul- 
ders (dry),  weighs 90  to  100  " 

One  cubic  ft.  filled  with  boulders  not  over 

six  inches  in  diameter  (dry)  weighs 95  to  105  " 


Auriferous  gravel  deposits  are  formed  on  all 
kinds  of  bed-rock,  such  as  granites,  limestones, 
slates,  and  quartzites,  and  even  sandstones.  The 
nature  of  the  bed-rock  rarely,  if  ever,  affects  the 


1 4  H  YDRA  ULJC  MINING. 

quality  of  the  deposit,  though,  as  will  Be  seen 
hereafter,  it  may  affect  its  economic  value. 

GOLD. 

The  precious  metal  is  of  a  fine  yellow  color 
when  chemically  pure,  and  weighs  about  nine- 
teen times  as  much  as  an  equal  bulk  or  volume 
of  water.  Hence 

One  culno  inch  of  gold  weighs 696  Ibs. 

One  cubic  foot        "  "     1204     " 

Its  value  per  standard  Troy  ounce  is  $20  67, 
and  per  pound  (Troy)  $248  04 

In  nature  gold  never  occurs  pure,  but  is  inva- 
riably accompanied  with  some  silver,  and  often 
with  other  metals.  In  this  condition  it  presents 
a  whitish  or  reddish  yellow  color,  according  as 
the  bulk  of  the  accompanying  metal  is  silver  or 
copper. 

The  metal  is  exceedingly  tenacious,  malleable, 
and  melts  at  a  temperature  of  2,016  deg.  Fan. 

In  practice  its  comparative  purity  is  expressed 
by  the  term  "fineness,"  and  this  is  estimated  on 
the  basis  of  1,000  as  a  unit  of  measurement. 


H )  DRA  ULIC  MINING.  I  5 

Thus,  a  mass  or  nugget  of  gold  containing  78 
per  cent,  of  gold,  18  per  cent,  of  silver,  and  4 
per  cent,  of  other  substances  will  be  said  to  be 
.780  (seven  hundred  and  eighty  thousandths) 
fine. 

In  the  gravel  deposits  gold  occurs  as  nuggets 
(masses  of  irregular  shape  and  size)  ;  shot-gold 
(rounded  pellets  like  very  small  bird-shot)  ; 
leaf-gold  (thin  sheets  sometimes  one-tenth  of  an 
inch  square)  ;  coarse  flat  gold  (same  size  as  the 
latter,  but  thicker)  ;  and  dust,  which  is  often  so 
fine  as  to  be  inappreciable  to  the  naked  eye. 
Occasionally  wire-gold  is  found,  but  that  is  rare. 
The  physical  qualities  of  this  metal  are  such 
that,  while  it  will  remain  almost  wholly  intact 
under  the  action  of  chemical  reagents,  it  is 
easily  affected  by  abrasion,  and,  if  carried  for 
considerable  distances  together  with  gravel  and 
ice,  is  ground  rapidly  to  the  finest  powder. 

It  does  not  always  follow  that  a  gravel  deposit 
containing  even  a  goodly  quantity  of  gold  per 
yard  can  be  worked  with  profit.  The  particles 
of  metal,  to  be  capable  of  being  saved  by  cheap 
mechanical  means,  must  possess  a  combination 


1 6  //  YDRA  ULIC  MINING. 

of  weight  and  shape  which  will  permit  the  ac- 
tion of  gravity  to  a. maximum  degree.  In  other 
words,  if  the  bulk  of  the  gold  in  a  deposit  is 
either  in  the  condition  of  a  very  fine  dust  or 
very  flat,  thin  scales,  it  will  float  away  and  resist 
the  most  careful  endeavors  to  precipitate  it. 


WATER. 

At  ordinary  temperatures  water  is  a 
colorless  liquid,  weighing  about  6&J-  Ibs.  per 
cubic  foot.  At  32  deg.  Fah.  it  becomes  a  solid, 
and  in  the  act  of  solidification  expands  one- 
twelfth  of  its  volume.  At  212  deg.  (sea-level) 
it  boils,  and  passes  ofl:  as  vapor.  Water  is 
slightly  compressible  at  a  pressure  of  4,500  Ibs. 
per  square  inch,  but  on  removal  of  the  force  re- 
turns instantly  and  completely  to  its  former  vol- 
ume. When  expanding  under  the  influence  of 
heat  or  cold  it  is  capable,  as  is  well  known,  of 
exerting  enormous  force. 

The  following  table  of  equalities  will  be  found 
at  times  useful: 


H  YDRA  ULIC  MINING.  I  / 

1  cubic  inch  of  water  weighs 086  Ibs. 

1     "     foot         "          •  "       62.5        " 

1     "     yard        "  "       1680.75      " 

1     "     foot  of  ice  "       57.3        " 

1  U.  S.  gallon  "       8.34      « 

The  standard  measure  for  water  in  hydraulic 
mining  is  the  miner's  inch. 

The  quantity  of  water  which  will  escape  from 
a  reservoir  through  an  aperture  in  its  side  1  inch 
square,  whose  centre  is  6  inches  below  the  con- 
stant level  of  the  water,  is  termed  a  miner's 
inch.  This  measure  is  necessarily  a  rough  one, 
and  has  doubtless  been  often  erroneously  ap- 
plied. The  aperture  should  have  no  tube  or 
conduit  leading  from  it,  and  its  section  through- 
out should  be  uniform  and  possess  practically  no 
length.  These  conditions  are  not,  however,  at- 
tained in  common  practice.  The  most  common 
illustration  of  the  miner's  inch  is  a  hole  1  inch 
square  through  an  inch  board.  In  this  case  the 
length  of  the  aperture  is  clearly  equal  to  its  dia- 
meter. Where  the  aperture  discharges  a  large 
number  of  inches  at  once  its  diameter  is  of 
course  much  larger,  and  the  proportion  of  its 
length  to  its  diameter  is  much  less. 


1 8  H  YDRA  ULIC  MINING. 

In  round  numbers  the  miner's  inch  has  the 
following  values  : 

Cubic  feet.          Pounds.          U.  8.  gal. 

Discharge  per  second .         .0271=  1.69=         0.2026 

min...        1.626    =        100.      =       11.99 

hour..       97.56      =      5937.      =     711.96 

day(12h.)1170.7       =    71250.      =8543.29 

day(24h.)2341.4        =142560.       =17095.78 

The  miner's  inch  as  a  standard  of  water  mea- 
surement is  very  defective.  In  the  early  days  of 
placer-mining,  when  the  water  was  owned  by 
one  set  of  people,  who  sold  it  in  small  quanti- 
ties to  another  set  (the  miners),  this  standard 
was  a  necessity.  At  present  it  would  be  better 
if  the  cubic  foot  could  be  used  as  a  measure,  but 
the  change  is  one  impossible  to  be  made. 


CHAPTER  II. 

GENERAL  METHODS  OF  PLACER-MINING. 

THE  general  theory  of  hydraulic  mining  com- 
prehends— first,  breaking  down  the  gravel ;  sec- 
ond, passing  it  through  sluice-boxes  while  held 
in  suspension  by  water;  and,  third,  cleaning  up 
the  gold  caught  in  the  boxes. 

The  pan,  rocker,  long  torn,  sluice,  boom,  and 
hydraulic  have  been  successively  adopted  in  al- 
most every  gravel-mining  district  in  America. 
Unfortunately,  exact  records  of  the  possible  work 
with  each  are  almost  unattainable,  and,  even  if 
they  were,  variations  in  the  character  of  the 
gravel  would  to  a  large  extent  nullify  their 
value.  The  following  comparative  table,  giving 
figures  of  work  performed,  first,  on  ordinary 
gravel,  which  is  quite  tractable,  and,  second,  on 
cemented  gravel,  which  is  perhaps  the  most  re- 
fractory known,  will  perhaps  be  of  value  to  the 


2O  HYDRAULIC  MINING. 

miner.  The  two  may  bo  regarded  as  extremes. 
The  table  shows  the  number  of  cubic  yards  of 
dirt  which  may  be  washed  per  day  of  10  hours 
per  man — in  the  first  two  cases  each  man  work- 
ing alone,  and  in  the  last  four  in  pairs,  or 
economically- arranged  gangs : 

Ordinary.  Cemented. 

By  the  pan 1  cu.  yd.  £  cu.  y«l. 

"       rocker 2       "  2        «' 

"       long  torn...            5  to  6       "  3  to  5         " 

"      sluice 10  to  20       "  6  to  12 

"       hydraulic ..  100  to  1000       "       100  to  1000        " 

"       boom unlimited.  unlimited. 

It  will  be  understood  by  every  miner  that  no 
exact  figures  can  be  given  in  a  comparison  of 
this  nature,  and  that  the  character  of  the 
ground  will  very  largely  affect  the  amount  of 
work  done.  With  the  pan,  which  will  hold 
from  fifteen  to  thirty  pounds  of  gravel,  only 
a  very  little  ground  can  be  washed  under  any 
circumstances.  If  the  ground  abounds  in  large 
boulders  which  can  be  removed  by  the  hand 
with  ease,  a  miner  will  wash  twice  as  much  as 
otherwise.  One  hundred  pans  are  considered  as 
a  good  day's  work  for  a  careful  operator.  The 


HYDRA  ULIC  MINING.  2  I 

same  consideration — that  of  boulders — applies 
to  the  work  in  a  rocker  and  long  torn.  The 
latter  permits  a  more  easy  and  thorough  break- 
ing np  of  cement,  and  the  water  generally 
being  supplied  automatically,  it  is  operated  at 
a  smaller  cost.  But  neither  arc  adapted  for 
operations  on  a  large  scale,  nor  in  any  ground 
carrying  less  than  three  to  five  dollars  per 
yard. 

The  ground -sluice  is  a  device  which  com- 
mends itself  for  banks  not  too  high  to  cause 
danger  from  caving,  and  when  a  good  grade 
in  the  pit  can  be  obtained.  The  unfavorable 
point  in  this  system  lies  in  the  fact  that  all 
boulders  must  be  moved  twice,  and  that  no 
clean-up  can  be  made  till  the  end  of  the  sea- 
son. In  consequence,  either  the  work  is  pro- 
longed, with  great  discomfort  to  the  men,  into 
the  period  of  cold  weather,  or  much  water  is 
allowed  perforce  to  run  to  waste. 

Whore  extensive  operations  are  contemplat- 
ed the  miner  has  to  decide  between  the  boom 
and  hydraulic,  or  a  favorable  combination  of 
the  two.  In  California  the  boom  is  wholly 


22  // 1 'DRA  ULIC  MINING. 

abandoned  in  favor  of  the  hydraulic,  and  in 
Colorado  it  is  rapidly  being  superseded.  Yet, 
as  a  system  of  placer-mining,  it  has  many 
strong  recommendations,  and.  according  to 
some  of  the  best  Colorado  authorities,  is  often 
the  superior  method.  It  seems  to  possess  most 
merits  when  either  the  water  is  very  abundant 
or  very  scarce. 

The  boom  will  undoubtedly  cave  more  ground 
per  day  and  at  a  less  cost  than  the  hydraulic, 
unless  it  is  a  very  hard  cement.  In  its  opera- 
lion  it  is  the  counterpart  of  the  work  of  nature 
in  natural  ravines.  For  the  purpose  of  clean- 
ing off  top  dirt  of  poor  quality  it  has  no  supe- 
rior, and  for  ground  carrying  no  leaf -gold  it  is 
claimed  by  some  to  be  greatly  preferable.  Much 
depends  upon  the  sluice  and  the  manner  of 
operating  it. 

But  where  the  ground  is  hard  and  force  is 
necessary  to  tear  it  to  pieces,  where  the  banks 
are  low  and  the  gravel  tenacious,  the  hydraulic 
is,  by  the  testimony  of  most  practical  miners, 
the  most  advantageous.  In  many  cases  the  two 
can  be  combined  with  most  beneficial  results. 


H  YDKA  ULIC  MINING.  2  3 

In  deciding  which  plan  to  adopt  the  miner  will 
do  well  to  bear  in  mind  the  principle  that  he 
is  working,  as  a  first  consideration,  to  make 
money — .not  only  to  tear  away  the  largest  pos- 
sible amount  of  gravel.  Consequently,  that 
method  or  combination  of  methods  is  the  cor 
rect  one  which  will  deliver  the  largest  quantity 
of  gravel  (with  its  gold)  at  his  head  box  in  the 
shortest  time — provided  always  that  he  has 
sluice  capacity  and  water  sufficient  to  wash  it 
thoroughly. 

In  nine  cases  out  of  ten  the  method  to  be 
adopted  is  decided  by  the  amount  of  water 
available  ;  and  if  the  supply  is  unlimited  (which 
is  very  rarely  the  case)  the  hydraulic  is  always 
better  than  the  boom,  if  the  two  cannot  be  used. 
The  quantity  of  work  possible  to  be  done  with 
the  hydraulic  varies,  of  course,  with  the  nature 
of  the  gravel,  the  size  of  the  stream,  and  the 
head.  A  very  sound  practical  authority  gives 
the  following  rough  estimates : 

No.  1  nozzle,  supplied  with  100  miners'  inches 
of  water,  under  a  head  of  100  feet,  assisted  by  a 


24  HYDRAULIC  MINING. 

ground-sluice  of  100  inches,  will  wash  600  cubic 
yards  per  day  ;  3  men. 

No.  4  nozzle,  supplied  with  700  inches,  under 
a  head  of  150  feet,  will  wash  3,000  cubic  yards 
per  day  ;  4  men. 


CHAPTER  IIL 

DIRECTIONS  FOR  THE  MINER. 

I  ATTEMPT  in  this  work  to  give  rales  and  di- 
rections for  solving  all  the  simpler  engineering 
problems  which  the  practical  hydraulic  miner 
(who  in  most  cases  is  unacquainted  with  higher 
mathematics)  will  have  presented  to  him.  To 
be  successful  the  miner  must  make  himself 
thoroughly  acquainted  with  the  contents  of  this 
chapter,  which  is  intended  to  be  explanatory  of 
such  mathematical  operations  as  will  be  noted. 
He  who  is  able  to  add,  subtract,  multiply,  and 
divide  will  find  nothing  in  this  book  beyond 
his  ability,  if  this  chapter  is  carefully  studied, 
and  if  the  same  hard  common  sense  and  intel- 
ligence which  in  all  other  matters  distinguishes 
the  American  miner  from. other  classes  of  work- 


26  HYDRAULIC  MIXING. 

ingmen  is  brought  to  bear  on  the  subject.  Hy- 
draulic mining  is  a  branch  of  engineering,  and 
because  its  operations  can  be  guided  wholly  by 
mathematical  rules  it  presents  so  much  of  cer- 
tainty and  so  little  of  risk.  Consequently,  the 
miner  who  desires  to  improve  nis  property  and 
increase  his  profits,  but  is  unable  from  various 
causes  to  obtain  the  assistance  of  an  experi- 
enced engineer,  will  certainly  find  it  to  be 
worth  his  while  to  gain  the  power  of  solving, 
alone  and  unaided,  a  majority  of  the  problems 
which  will  be  presented  for  consideration  in 
the  ordinary  course  of  his  business. 

I  will  call  the  reader's  attention,  therefore,  to 
the  following  subjects  : 

1.  The  use  of  decimals  ; 

2.  The  method  of  transforming  fractions  into 
decimals  ;  and, 

,  3.   The  principle  of  expressing  the  terms  of  a 
problem  in  a  uniform  and  correct  manner. 

DECIMALS. 

The  decimal  system  is  a  method  of  numerical 
expression   based   upon  a  division  of   the  unit 


HYDRAULIC  MINING.  2/ 

one  (1)  by  ten  (10)  or  multiples  of  ten  (as,  100, 
1,000,  10,000).  For  example,  instead  of  say- 
ing  one-half  (£)  say  five-tenths  (T5¥),  and  instead 
of  saying  one-quarter  (J)  say  twenty-five  one- 
hundredths  (-$/V).  The  system,  however,  does 
not  stop  here,  but  includes  a  system  of  nota- 
tion which  does  away  completely  with  the  form 
of  the  fraction  —  thus  : 

-f-0  is  written  .5 

T¥TT  .25 

fVo  "  .84 

T«O  "  -012 

yVoV  w  -611 


Toifoo  "  .00014 

Hence,  to  write  down  a  decimal  fraction  deci- 
mally, follow  this  rule  : 

1.  Eeplace  the  figure  1,  which  is  always  the 
first  figure  of  the  lower  part  of  the  fraction,  by  a 
dot  (  .  ). 

2.  Rub  out  as  many  of  the  last  figures  of 
the  lower  part   of    the  fraction   as   there    are 


28  HYDRAULIC  MINING. 

figures  in  the  upper  part,  and  place  these  figures 
in  the  room  of  the  figures  rubbed  out. 

For  instance,  to  express  decimally  the   frac- 
tion  four    hundred    and    eleven    ten-millionths 


Replacing  the  1  by  a  dot,  we  have      .0000000. 

Second,  as  there  are  three  figures  in  the  upper 
part  of  the  fraction,  we  rub  out  the  last  three 
ciphers  of  the  above,  and  replace  them  with  411, 
making  .0000411 

Again,  express  decimally  three  hundred  Jind 
one  thousandths  (yVoV)' 

Replacing  the  1  by  a  clot  gives  .000 

and  placing  in  the  301  gives  .301 

Again,  express  thirty-two  tenths  (ff).  This 
fraction  is  evidently  the  same  as  three  and  two- 
tenths  (Sy2^),  which,  treated  by  the  rule,  gives  3.2. 

The  addition  of  decimals  is  performed  exactly 
as  any  other  addition.  Place  the  two  or  more 
quantities  under  each  other,  taking  care  that  the 
decimal-points,  the  dots  (  .  ),  are  in  a  line,  and 
place  the  decimal-point  in  the  answer  or  result 
in  the  same  position,  thus: 


H  YDRA I  LIC  MINING.  2Q 

.0104 

3.26 
.192 
114. 

117.4624 

In    subtracting    adopt    precisely    the    same 

course,  thus: 

1.242 

.012 
1.230 

,61306 
.4 


.21306 

In  multiplying  place  the  quantities  in  the  or- 
dinary way,  multiply  as  usual,  and  point  off  as 
many  figures  in  the  result  as  there  are  decimals 
in  the  two  quantities  multiplied,  thus: 

1.264 
.06 

.07584 


.SO  HYDRAULIC  MINING, 

Agai  n : 

.1103 
.17014 


4412 
1103 

7721 
1103 

.018766442 

The  division  of  decimals  is  performed  as  fol- 
lows: 

Set  down  the  figures  as  in  the  ordinary  style 
of  long  division.  Annex  to  the  dividend  (the 
quantity  to  be  divided)  first  as  many  ciphers  as 
may  be  necessary  to  make  the  number  of  deci- 
mal figures  in  the  dividend  equal  in  number  to 
those  in  the  divisor,  and,  second,  as  many  more 
as  may  be  necessary  to  obtain  a  figure  large 
enough  to  divide. 

Divide  as  in  the  ordinary  method. 

Point  oft'  in  the  result  as  many  places  for  de- 
cimals as  the  number  of  decimals  in  the  dividend 
exceeds  those  in  the  divisor. 


HYDRA  ULIC  MINING.  3 1 

NOTE. — If  the  divisor  or  dividend  consists  of 
decimals  commencing  with  a  cipher  or  several 
ciphers  (as,  .0218  or  .00014),  these  ciphers  may  be 
wholly  disregarded  in  the  operation  of  division. 

The  following  examples  cover  all  cases  : 
(a)  When  the  divisor  is  larger  than  the  divi- 
dend— as,  to  divide  1.265  into  .04: 

1.265).04000000(3162 
3795 

2050 
1265 

7850 
7590 

2600 
2530 


In  this  case,  there  being  8  decimals  in  the  di- 
vidend and  3  in  the  divisor,  the  difference  5  will 
be  the  correct  number  for  the  quotient  or  an- 
swer, which,  instead  of  being  3162,  will  be  .03162. 


32  HYDRAULIC  MINING. 

(b)  When  the  divisor  is  less  than  the  dividend — 
as,  to  divide  .142  into  4.6: 

.142)4.600(32 
426 

340 

284 

There  being  an  equal  number  of  decimals  in 
both  divisor  and  dividend  in  this  case,  the  quo- 
tient remains  unaltered  as  32.  But  if,  instead  of 
annexing  two  ciphers,  we  had  annexed,  say,  six, 
the  quotient  would  have  been  323943,  we  would 
have  had  four  more  decimals  in  die  dividend  than 
in  the  divisor,  hence  the  result  would  have  been 
32.3943. 

In  the  division  of  decimals,  ciphers  may  be  an- 
nexed to  any  extent  desirable  until  no  remainder 
occurs;  this  makes  the  division  perfect.  Other- 
wise it  is  an  approximation.  But  in  all  calcula- 
tions except  those  of  a  most  delicate  nature  it  is 
sufficiently  accurate  to  annex  only  enough  ci- 
phers to  produce  three  decimal  figures  in  the 
result. 


H  YDRA  ULIC  MINING.  3  3 

(c)  \Vhere  ciphers  are  prefixed  to  dividend  or 
divisor,  or  both,  a  study  of  the  following  opera- 
tion will  explain  the  method.  Thus,  to  divide 
.0014  into  .0000403  : 

.0014).  0000403  (28 
28 

123 

112 

There  being  7  decimals  in  the  dividend  and 
4  in  the  divisor,  the  answer  should  contain  the 
difference,  or  3  figures,  giving,  in  place  of  28, 
the  quantity  .028. 

TRANSFORMATION     OF     FRACTIONS     INTO 
DECIMALS. 

When  a  problem  under  consideration  contains 
fractions  it  is  always  necessary  to  reduce  these 
to  decimals.  This  is  done  by  simply  dividing 
the  numerator  of  the  fraction  (the  top  figure) 
by  the  denominator  (the  bottom  figure).  Thus, 
to  reduce  J  to  decimals  divide  1  by  2  =  .5  ;  or  to 
reduce  -f,  divide  3  by  8  =  .375  ;  or  to  reduce  J, 


34  HYDRAULIC  MINING. 

divide  3  by  4=.75.     The  division  need  not  be 
carried  to  more  than  three  figures. 

This  must  be  done  in  all  cases.  As  an  exam- 
ple, if  the  grade  of  a  flume  is  found  by  experi- 
ment to  be  3^  inches  per  box,  the  fraction  is 
to  be  reduced  to  decimals  by  dividing  5  by  12, 
thus  : 

12)5.000(416 
48 

20 
12 

80 

72 

Pointing  off  the  result  (416)  according  to  the 
rule  of  division  of  decimals,  the  grade  is  found 
to  be  3.416  inches  per  box. 

THE    PRINCIPLE    OF    EXPRESSING    THE    TERMS    OF 
A    PROBLEM    UNIFORMLY. 

At  the  beginning  of  a  problem  it  is  necessary 
to  reduce  all  the  elements  to  the  right  shape  and 
form.  If  this  is  done  confusion  will  be  avoided. 


HYDRAULIC  MINING.  3.5 

If  it  is  not  done  the  results  will  be  false  almost 
invariably.  Hence, 

Express  perimeter,  lengths  of  flumes,  ditches, 
piping,  head,  diameters,  etc.,  in  linear  feet  and 
decimals  of  a  foot. 

Express  areas  (such  as  sections  of  flumes  and 
piping,  and  mouths  of  nozzles)  in  square  feet 
and  decimals  of  a  foot. 

Express  discharge  in  cubic  feet  per  second. 

Express  velocity  in  linear  feet  per  second. 

Express  grade  in  decimals  of  a  foot  per  linear 
foot. 

Thus,  discharge  from  a  flume  or  pipe,  which 
is  frequently  given  in  miners'  inches,  should  be 
reduced  to  cubic  feet  (see  Miner's  Inch)  ;  grade, 
which  is  generally  expressed  in  inches  per  box 
(12  feet)  or  inches  per  rod  (16  feet),  must  inva- 
riably be  altered  to  feet  per  foot ;  as,  for  in- 
stance, a  grade  of  1  inch  per  box  equals  1  inch 
per  12  feet,  or  -fa  of  an  inch  per  1  foot.  But  112- 
of  an  inch  equals  y^  of  a  foot,  which,  reduced 
to  decimals,  equals  .007  of  a  foot  nearly.  The 
correct  mode  of  expression,  therefore,  will  be 
.007  feet  ner  foot. 


36  HYDRAULIC  MINING. 

Velocity  must  be  expressed  in  feet  per  second, 
and  perimeters  in  decimals  of  a  foot.  A  flume 
having  a  perimeter  of  20  inches  measures  If  of 
a  foot.  Reducing  this  to  decimals,  we  have,  in 
place  of  20  inches,  1.666  feet. 

DEFINITIONS. 

The  subjoined  definitions  and  explanations 
will  be  found  necessary  to  a  perfect  understand- 
ing of  the  technical  phrases  used  in  succeeding 
pages.  The  reader  is  therefore  invited  to  im- 
press on  his  mind  the  exact  meaning  and  value 
of  each  term  defined : 

Mass. — The  quantity  of  matter  which  a  body 
contains — irrespective  of  whether  that  quantity 
be  diffused  through  a  large  space,  through  the 
influence,  for  example,  of  heat  (as  in  the  case 
of  steam) ;  or  compressed  into  a  small  space, 
through  the  influence,  for  example,  of  cold  (as 
in  the  case  of  ice) — is  called  its  mass. 

Volume. — The  amount  of  space  occupied  by  a 
body  is  denominated  its  volume. 

Weight. — When  a  body  is  freely  acted  upon  by 
gravity,  but  is  prevented  from  moving  by  some 


HYDRAULIC  MINING.  37 

supporting  obstacle,  the  pressure  on  the  point 
of  support  is  termed  its  weight. 

Jet. — A  jet  is  the  mass  of  water  escaping  from 
a  vessel  through  an  orifice  in  its  side  or  bottom, 
which  orifice,  of  course,  must  be  below  the  level 
of  the  water. 

Flow. — The  volume  of  water  which  escapes 
from  a  vessel  through  an  orifice  (which  may  be 
wholly  or  partly  under  the  water)  in  any  given 
time  is  its  flow  for  that  time. 

Velocity. — The  distance  passed  over  by  any 
given  mass  of  water  in  any  given  time  is  called 
its  velocity.  The  direction  of  the  motion  is 
immaterial. 

Head. — The  vertical  distance  between  the  level 
of  standing  water  in  -i  reservoir,  and  the  centre 
of  the  orifice  from  which  it  flows  into  the  air, 
is  called  its  head. 

Wet  Perimeter. — If  a  flume  or  ditch  is  20 
inches  wide,  6  inches  deep,  and  full  of  water, 
its  wet  perimeter  is  20+  6+6=32  inches.  If 
of  the  same  dimensions,  but  only  containing 
3  inches  of  water,  the  wet  perimeter  is  20+3 
-j-3=26  inches.  The  same  flume  again,  if 


38  H  YDRA  ULJC  MINING. 

empty,  has  no  wet  perimeter  at  all.  In  other 
words,  the  wet  perimeter  of  a  water- channel  is 
the  length  of  so  miicli  of  its  base  and  sides  as  is 
wetted  by  the  water.  This  measurement  deter- 
mines friction. 

Friction. — When  one  body  slides  upon  an- 
other, the  inequalities  and  roughnesses  of  the 
two  surfaces  interlock  and  cause  a  resistance, 
which  is  termed  friction.  If,  now,  the  sliding 
body  has  not  sufficient  weight  and  cohesion  to 
create  abrasion  or  wear  among  these  irregulari- 
ties and  roughnesses,  the  degree  of  friction  which 
arises  bears  a  well-known  proportion  to  the 
weight  of  the  sliding  body.  This  is  the  case 
when  water  slides  along  the  floor  of  a  flume  or 
ditch,  and  the  proportion  of  friction  developed 
to  the  weight  of  the  water  is  called 

THE    CO-EFFICIENT    OF   FRICTION. 

This  co-efficient,  of  course,  varies  as  the  water 
is  muddy  or  clear,  or  as  the  flume  floor  is  rough 
or  smooth.  It  is  however,  wholly  independent 
of  the  areas  of  the  surfaces  in  contact.  In  other 
words,  two  flumes  of  different  size,  if  made  of 


HYDRAULIC  MINING.  39 

the  same  quality  of  lumber  and  carrying  similar 
water,  will  develop  identical  co- efficients  of  fric- 
tion— the  proportion  of  friction  to  the  moving 
weights  will  be  the  same.  But  the  weights  of 
water  in  each  being  different,  the  amount  of  fric- 
tion developed  in  the  larger  flume  will  be  greater 
than  in  the  smaller. 

Momentum. — The  quantity  of  force  which  a 
body  in  motion  is  capable  of  exerting  when 
stopped  suddenly  is  called  its  momentum.  Proba- 
bly the  best  illustration  of  this  is  the  power  ex- 
hibited by  a  jet  of  water  when  it  strikes  a  bank 
of  gravel.  It  may  be  measured  by  multiplying 
the  weight  of  the  striking  body  by  the  velocity 
'  at  which  it  moves.  For  example:  A  nozzle  de- 
livering a  stream  of  water  3  inches  in  diameter, 
with  a  velocity  of  150  feet  per  second,  will  hurl 
against  a  bank  every  second  a  force  equal  to  the 
weight  of  a  column  of  water  3  inches  in  diame- 
ter and  150  feet  high,  multiplied  by  150,  or  3-H 
tons  nearly.  But  it  is  to  be  remembered  that 
this  is  the  amount  of  force  developed  at  the 
mouth  of  the  nozzle  only.  Immediately  on 
passing  into  the  air  the  stream  of  water,  acted 


4O  HYDRAULIC  MINING. 

upon  by  the  force  of  gravity  and  the  resistance 
of  the  air,  and  further  weakened  through  its  own 
disintegration,  becomes  less  powerful.  At  a  suf- 
ficiently great  distance  from  the  mouth  of  the 
nozzle  the  velocity  will  be  wholly  lost,  and  no 
force  or  power  remains  except  that  due  to  the 
weight  of  each  particle  of  water  under  the  influ- 
•ence  of  gravity.  Again,  it  is  not  to  be  thought 
that  if  a  gravel-bank  is  struck  with  the  force 
above  mentioned  34£  tons  of  earth  must  be 
moved  per  second.  This  statement  appears  to 
be  unnecessary,  though  it  may  be  logically  de- 
duced from  the  first,  unless  it  be  remembered 
that  vast  quantities  of  force  must  be  expended 
in  destroying  the  cohesion  of  the  gravel  and 
overcoming  its  inertia.  Once  in  a  state  of  mo- 
tion, the  force  transmitted  from  the  nozzle  to 
the  gravel  would,  if  the  force  could  be  applied 
.at  a  point  which  would  equally  affect  the  whole, 
give  it  as  rapid  motion  as  the  water,  less  fric- 
tion. But  this  can  never  be  accomplished  in 
practice. 

MENSURATION. 

A  few  questions  in  mensuration  will  arise  in 


HYDRAULIC  MINING.  41 

working  the  problems  presented  in  the  following 
pages.     These  are  as  follows  : 

1.  To  find  the   Area   of  a    Circle. — Multiply 
the  diameter  (in  inches)  by  the   decimal   3.14 
and  the  product  by  one-quarter  of  the  diameter. 
The  result  will  be  the  area  in  square   inches. 
Divide  this  by  144,  and  the  result  will  be  the 
area  in  square  feet. 

EXAMPLE. — What  is  the  area  of  a  circle  18 
inches  in  diameter  ? 

16  multiplied  by  3.14=50.24  multiplied  by  4 
(which  is  one-quarter  of  the  diameter)  =201. 06 
square  inches,  which  divided  by  144=  1.32  square 
feet. 

2.  To  find  the  Area  of  a  Section  of  a  Flume 
with    Straight    Sides. — Multiply  the   width   of 
bottom  (in  inches)   by  the  height  of   sides   (in 
inches);  the, product  will  be  the  area  in  square 
inches,  which,  divided  by  144,  gives  the  area  in 
square  feet. 

EXAMPLE. — What  is  the  area  of  a  section  of  a 
flume  20  inches  wide  and  15  inches  high  ? 

20  multiplied  by  15=300,  which  divided  by 
144=2.08  square  feet. 


42  ff\  DRA  UIJC  MINING. 

3.  To  find  the  Area  of  the  Section  of  a  Ditch 
with  Sloping  Sides. — Add  together  the  width  at 
top  and  bottom  (in  inches),  multiply  this  sum 
by  the  depth  (in  inches),  and  divide  the  result 
by  2.     The  quotient,  divided  by  144,  will  be  the 
area  in  square  feet. 

EXAMPLE. — What  is  the  area  of  the  cross-sec- 
tion of  a  ditch  60  inches  wide  at  the  top,  36 
inches  at  the  bottom,  and  12  inches  deep  ? 

60  plus  36  =  96,  which  multiplied  by  12-1152, 
and  this  divided  by  2=576  square  inches,  which 
divided  by  144=4  square  feet. 

4.  To  find  the  Area    of  the  Cross -Section  of  a 
Ditch  whose  Sides  slope  to  a  Point  at  the  Bot- 
tom.— Multiply  the   width    (in   inches)    by    half 
the  depth  (in   inches),  and  divide   the  product 
by  144.     The  result  is  the  area  in  square  feet. 

EXAMPLE. — What  is  the  area  of  a  pointed 
ditch  60  inches  wide  and  18  inches  deep  in  the 
centre  ? 

60  multiplied  by  9  (half  the  depth)  =  540 
square  inches,  which  divided  by  144=3.75 
square  feet. 


CHAPTER  IV. 

THE  PROPERTIES  OF  WATER. 

IN  hydraulic  mining  the  properties  of  water 
are  to  be  considered  in  but  two  conditions: 

(a)  When  at  rest — as  in  the  case  of  dams,  re- 
taining walls,  and  pressure-boxes  ;  and 

(if))  When  in  motion — as  in  ditches  and 
flumes, 

WATER    AT   REST. 

The  three  principles  here  laid  down  will  be 
worth  consideration  by  the  miner  who  desires  to 
work  understandingly. 

1.  Water  at  Rest  transmits  Pressure  equally 
in  all  Directions. — If  a  pressure  of  100  Ibs.  is 
exerted  on  the  entire  surface  of  the  water  in  a 
reservoir  whose  section  is  10  square  feet,  this 
pressure  is  transmitted  in  its  entirety  not  only 
to  the  base,  but  to  every  10  square  feet  of  its 
sides.  Thus,  if  the  interior  surface  of  the  reser- 


44  HYDRAULIC  MINING. 

voir  (base  and  sides)  measures  250  square  feet, 
and  a  pressure  of  100  Ibs.  is  placed  on  the  water- 
surface  (of  10  square  feet),  the  base  and  walls 
will  receive  a  total  pressure  of  2,500  Ibs.  Or  if 
the  box  be  so  closed  at  the  top  as  to  leave  but 
one  square  foot  of  water  exposed,  and  if  a  pres- 
sure of  100  Ibs.  be  applied  on  this  one  square 
foot,  an  equal  pressure  will  be  transmitted  to 
every  square  foot  of  interior  surface,  and  the 
total  will  consequently  be  25,000  Ibs.  Or,  to 
illustrate  this  remarkable  property  still  more 
thoroughly,  suppose  the  top  of  the  vessel  to  be 
covered  with  the  exception  of  one  square  inch. 
If  on  this  a  pressure  of  100  Ibs.  is  placed,  every 
square  inch  of  interior  surface  will  be  pressed 
outward  with  this  weight,  which,  for  the  size 
box  under  consideration,  would  amount  alto- 
gether to  1,800  tons. 

This  is  the  principle  utilized  in  the  hydraulic 
press. 

2.  The  Pressure  exerted  by  Water  on  the 
Horizontal  Bottom  of  a  Vessel  is  wholly  inde- 
pendent of  the  shape  of  the  vessel^  and  is  equal 
to  the  weight  of  a  column  of  water  whose  base  is 


H }  DRA  ULIC  MINING.  4$ 

the  area  of  the  horizontal  bottom,  and  whose 
height  is  equal  to  the  depth  of  the  liquid. 

3.  The  Pressure  of  Water  on  the  sides  of  a 
Vessel  is  equal  to  the  weight  of  a  column  of 
water  whose  base  is  equal  to  the  area  of  the  side, 
and  whose  height  is  equal  to  one-half  the  depth 
of  the  liquid. 

Owing  to  this  law  the  pressure  on  the  walls 
and  base  of  a  cubical  vessel  is  equal  to  three 
times  the  weight  of  the  water  contained. 

The  two  principal  problems  in  hydraulic  min- 
ing arising  under  the  head  of  water  at  rest  are 
those  connected  with  the  construction  of  dams 
and  reservoirs  and  water-boxes. 

Keferring  to  the  third  principle  just  enun- 
ciated, it  will  be  seen  that  the  pressure  on  any 
surface  under  water  depends  upon  two  things — 
the  depth  of  water  and  the  area  of  the  surface 
pressed.  For  example,  what  will  be  the  pres- 
sure against  the  inner  slope  of  a  dam  50  feet 
long,  12  feet  wide,  and  12  feet  deep  at  the  bot- 
tom? Multiply  the  area  of  the  slope  (50x12= 
600)  by  the  average  vertical  depth  in  feet  of  the 
centre  of  gravity  of  the  slope  (6)  =3, 600,  and 


46  HYDRAULIC  MINING. 

multiply  this  by  62.5  (the  weight  of  a  cubic  foot 
of  water)  =225,000  Ibs. 

It  will  be  noted  that  the  pressure  is  not  a 
pound  greater  if  the  water  reaches  back  from  the 
face  of  the  dam  for  miles,  than  if  it  were  a  reser- 
voir only  a  few  feet  broad.  Hence,  if  a  reservoir 
is  built  simply  for  storage,  make  it  large  and 
shallow  rather  than  small  of  area  and  deep. 
The  loss  by  solar  evaporation  will,  it  is  true,  be 
much  grenter,  but  this  disadvantage  will  be 
counterbalanced,  first,  by  the  small  leakage ; 
second,  by  the  cheapness  of  the  dam  ;  and,  third, 
by  the  great  safety  of  the  construction.  A 
miner  cannot  go  to  his  work  under  more  de- 
pressing circumstances  than  with  the  thought 
that  at  the  head  of  the  gulch  in  which  he  is  im- 
prisoned is  a  dam  whose  embankment  of  15  or 
20  feet  in  height  may  at  any  time  give  way  and 
destroy  not  only  himself  and  comrades,  but 
every  trace  of  improvements  that  have  been  the 
labor  of  years. 

Probably  the  best  and  safest  embankment, 
where  there  is  no  carpentry  or  masonry,  is  that 
one  which  is  modelled  on  the  plan  of  the  beaver- 


HYDRAULIC  MINING.  47 

dam.  This  is  a  familiar  sight  in  the  West,  and 
its  details  can  be  easily  studied.  The  beaver- 
dam  is  seldom  if  ever  "known  to  give  way,  and 
this  quality  of  stability  is  what  is  of  all  things 
most  desirable. 

The  water  or  pressure  box  has  three  uses.  It 
determines  permanent  and  steady  head  ;  it  offers 
an  opportunity  to  clear  the  water  from  gravel 
and  other  debris  before  passing  it  into  the  pipe, 
and  it  should  be  the  means  of  freeing  it  from  a 
large  portion  of  the  air  which  it  absorbs  while 
travelling  at  a  high  velocity. 

Construction. — The  pre.?sure-box  should  be  a 
deep  vessel,  with  a  pyramidal  bottom  pointing 
downward  and  provided  with  a  trap.  This,  on 
being  opened  from  time  to  time,  will  clear  out 
gravel  and  sand  which  has  collected  in  the  bot- 
tom, and  which,  if  allowed  to  accumulate,  would 
in  time  rise  to  the  level  of  the  outflow.  The 
pressure-box  is  best  built  when  its  height,  ex- 
clusive of  pyramidal  bottom,  is  three  times  its 
greatest  width.  The  section  should  be  longer 
one  way  than  another.  It  should  have  a  lip 
overflow  on  one  of  the  short  sides,  and  the  water 


48  HYDRAULIC  MINING. 

should  enter  the  box  at  the  centre  of  its  top, 
and  from  the  same  side  as  the  discharging-lip. 
All  screening  should  be  done  in  the  flume.  A 
partition  reaching  down  below  the  outflow,  and 
parallel  with  the  longest  sides,  is  highly  recom- 
mended by  good  authorities.  The  discharge- 
hole  should  be  two-thirds  of  the  distance  from 
top  to  bottom  (no  increase  of  power  is  gained  by 
placing  it  at  the  bottom),  and  should  be  in  one 
of  the  long  sides.  If  these  directions  are  ob- 
served a  large  quantity  of  the  gravel  unavoidably 
carried  into  the  box  will  be  prevented  from  pass- 
ing into  the  pipe,  much  of  the  air  will  also  be 
kept  out,  and  a  steady  and  even  head  will  be  se- 
cured. 

We  have  now  to  consider  only  the  strength  of 
the  box.  That  this  is  an  important  point  may 
be  judged  by  the  fact  that  if  its  height  is  12  feet, 
and  its  section  3  by  4  feet,  it  will  have  to  sustain 
a  pressure  of  not  less  than  35  tons. 

MEASURING   THE   WATER   OF   STREAMS. 

If  the  channel  of  the  stream  has  a  moderately 
even  outline,  measure  its  depth  at  regular  in- 


HYDRA  ULIC  MINING  49 

tervals  from  shore  to  shore.  Add  all  these 
depths  together,  and  divide  the  sum  by  the 
number  of  soundings.  An  average  depth  is  thus 
gained.  Calculate  then  the  area  of  the  section 
according  to  Rule  2,  page  41.  Measure  the  velo- 
city by  means  of  a  float,  and  make  the  test  about 
half-way  between  the  bank  and  the  centre.  Mul- 
tiply the  area  by  the  velocity,  and  the  product 
will  be  the  flow.  Of  course  the  test  for  velocity 
should  be  made  at  the  same  point  where  the 
measurements  for  depth  are  made,  and  a  place 
on  the  stream  should  be  selected  for  both  where 
the  banks  are  as  nearly  parallel  as  may  be,  ana 
where  the  current  and  flow  is  the  most  tranquil. 

EXAMPLE.— A  stream  is  24  feet  broad,  and  ten 
soundings  at  every  two  feet  on  a  line  from  bank 
to  bank  give  2,  6,  8,  9,  7,  11,  11,  10,  9,  and  2 
inches  as  the  depths.  The  average  velocity  as 
determined  by  float  is  4  feet  per  second.  What 
is  the  flow  ? 

The  sum  of  the  10  soundings  is  75  inches, 
which  gives  an  average  depth  of  7.5  inches, 
equal  to  .625  of  a  foot.  The  area  of  the  section 
then  is  24  multiplied  by  .625  =  15  square  feet. 


5O  HYDRAULIC  MINING. 

The  velocity  being  4  feet  per  second,  the  flow  is 
equal  to  15  multiplied  by  4=60  cubic  feet  per 
second. 

If  the  stream  runs  over  a  bottom  so  irregular 
tli at  an  average  depth  cannot  be  gained  or  an 
average  velocity  measured,  there  is  no  recourse 
but  to  construct  an  artificial  channel  having  no 
grade,  into  which  it  may  be  turned  while  mea- 
sures are  made.  The  same  rule  applies  in  this 
case  as  before,  and  it  should  be  understood'  that 
in  both  the  results  are  very  rough  approxima- 
tions. To  reduce  the  result  to  miners'  inches 
refer  to  the  table  of  equalities,  page  18. 


CHAPTER  V. 

CONSTRUCTION  OF  WATER-WAYS. 

WHEIST  the  miner  has  measured  the  stream 
from  which  he  is  to  draw  his  water-supply,  and 
has  determined  that  point  where  he  will  tap  it, 
he  is  prepared  to  consider  the  question  of  water- 
channels.  These  may  be  of  three  kinds — the 
ditch,  the  wooden  flume,  and  the  iron  pipe.  The 
ditch  is  the  most  indestructible,  the  cheapest, 
and  the  easiest  to  repair.  Instead  of  deteriorat- 
ing, it  improves  in  condition  year  by  year  if 
carefully  built.  On  the  other  hand,  more  water 
is  lost  by  evaporation,  and  in  stormy  seasons  it  is 
subject  to  injury  by  overflows,  land-slides,  caves, 
etc.,  etc.  The  wooden  flume  eliminates  the  ele- 
ment of  loss  by  leakage,  but  not  by  evaporation. 
It  occupies  the  middle  ground  in  point  of  cost, 
but  requires  much  watching.  It  is,  moreover, 
the  most  easily  destroyed  by  fire  and  flood.  The 
iron  pipe  prevents  all  loss  on  the  way,  is  most 


52  HYDRAULIC  MINING. 

easily  cared  for,  and  costs  the  most.  It  is  seldom 
considered  to  be  the  best  method  of  water  trans- 
portation, except  when  a  necessity,  as  in  the  case 
of  siphon-bends  or  very  steep  grades,  or  on  the 
rocky  side  of  mountains  where  ditching  would 
be  costly. 

It  is  generally  desirable  to  have  the  least  pos- 
sible fall  in  a  water  channel,  or,  in  other  words, 
to  bring  the  water  to  as  high  a  point  of  the 
ground  to  be  worked  as  circumstances  will  allow. 
As  the  friction  of  the  sides  and  bottom  of  a 
channel  retards  the  flow,  and  necessitates  a  high- 
er grade  than  would  be  necessary  if  there  were 
none,  it  becomes  of  importance  to  decrease  this 
element  as  much  as  possible.  On  this  score 
wood  and  iron  water-ways  present  decided  ad- 
vantages, owing  to  their  comparative  smooth- 
ness. In  any  case,  however,  the  quantity  of 
friction  developed  depends  upon  the  wet  perime- 
ter of  the  channel  used.  The  following  law  will 
therefore  be  found  of  service  : 

TJie  least  wet  perimeter  that  will  hold  or  carry 
a  given  volume  is  attained  when  the  width  of  bot- 
tom is  from  If  to  2%  times  the  depth  of  the  side*. 


HYDRAULIC   MINING.  53 

For  example,  a  channel  having  a  cross- section 
of  510  square  inches  will  develop  the  least  amount 
of  friction  when  its  dimensions  are  15  by  34,  or 
17  by  30,  or  somewhere  between  these  measure- 
ments. 

A  knowledge  of  this  fact  will  be  found  ser- 
viceable in  constructing  flumes.  The  least  peri- 
meter, of  course,  requires  the  least  lumber,  and 
many  thousand  or  million  feet  may  be  saved  in 
a  long  flume  by  building  in  the  correct  pro- 
portion. 

When  the  head  of  the  flume  is  above  timber- 
line,  or  in  high  altitudes  where  ice  forms  early  in 
the  fall,  it  is  an  advantage  in  many  respects  to 
have  it  so  narrow  in  width  that  an  ice-crust  can 
easily  form  itself  from  bank  to  bank.  If  this  is 
secured  water  will  often  flow  a  month  or  six 
weeks  longer  than  otherwise.  The  reasons  are 
obvious. 

In  making  the  preliminary  survey  of  a  placer- 
claim  a  sound  authority  advises  as  follows :  First, 
lay  off  the  dump  ;  second,  decide  how  much 
grade  and  fall  to  give  the  sluices  ;  and,  third, 
find  the  least  fall  necessary  between  source  of 


54  HYDRAULIC  MINING. 

water  and  water-box.  The  remaining  distance 
will  then  be  the  greatest  head  attainable.  The 
suggestion  is  pertinent,  because  it  brings  to  mind 
the  fact  that  a  good  dump  and  an  abundant 
grade  for  sluices  are  fully  as  necessary  for  econo- 
mical gravel-washing  as  a  heavy  head  of  water. 

When  the  linear  distance  be;  ween  the  sources 
of  supply  and  the  water-box  is  determined,  and 
the  least  fall  that  will  carry  the  water  ascer- 
tained (after  considering  the  questions  of  fric- 
tion, evaporation,  and  leakage),  the  grade  per 
foot  is  found  by  dividing  the  total  fall  in  feet  by 
the  total  length  in  feet.  Multiplying  the  result 
(which  will  generally  be  a  decimal)  by  100  or 
1,000 -will  give  the  grade  per  100  or  1,000  feet. 
Having  now  the  grade  per  foot  and  the  quantity 
of  water  to  be  carried  (as  determined  by  gaug- 
ing the  stream  or  streams  tapped  by  the  ditch  or 
flume — the  proper  deductions  having  been  made 
for  leakage  and  evaporation),  the  area  of  cross- 
section  of  the  water-way  may  be  determined  by 
the  rule  for  the  determination  of  the  least  wet 
perimeter,  which  has  just  been  given. 

Solar  evaporation  is  very  active  at  high  alti- 


HYDRAULIC  MIMXG.  55 

tudes.  The  ordinary  figures  representing  loss 
through  evaporation  (TV  to  -f^  of  an  inch  of  sur- 
face per  day)  are  much  too  small  for  ditches 
above  an  altitude  of  6,000  feet.  Evaporation 
also  proceeds  much  more  rapidly  in  shallow  water 
than  in  deep,  and  when  the  velocity  is  high. 
Experiments  made  during  1877  on  the  12-mile 
wooden  flume  of  the  Fuller  Company,  on  the 
Swan  River,  Colorado,  indicated  a  loss  of  from 
10  to  18  per  cent,  daily.  This  flume  is,  how- 
ever, an  extreme  case,  being  about  10,000  feet 
above  sea-level.  Probably  an  inch  of  surface 
would  be  an  average  loss.  , 

Leakage  occurs  most  extensively  in  gravelly 
soils.  From  1  to  5  inches  of  surface  per  day 
are  extreme  losses,  with  an  average,  perhaps,  of 
about  2  inches,  which  it  will  be  always  safe  to 
count  on,  except  in  old  ditches.  A  high  velo- 
city decreases  loss  through  the  soil. 

Water-channels  of  uniform  section  should  al- 
ways have  a  uniform  grade.  Otherwise  there  will 
be  an  accumulation  in  some  points  and  a  thin- 
ning-out in  others,  with  deposits  of  sand  and 
silt  in  the  latter  case,  and  in  each  case  with  in- 


56  HYDRAULIC  MINING. 

creased  danger  of  breakage.  It  will  also  be 
found  highly  advantageous  in  earth  ditches  to 
have  a  complete  system  of  waste-weirs  to  carry  off 
surplus  waters  occasioned  by  floods  and  to  lessen 
the  damage  of  breaks.  These  should  be  put  in 
just  below  wherever  a  new  stream  falls  into  the 
diich,  and  just  above  those  places  where,  by  rea- 
son of  a  shelly  or  crumbly  soil,  the  ditcli  is  weak. 
A  break  is  bad,  not  only  because  it  must  be  re- 
paired, but  because  while  being  mended  all  min- 
ing operations  must  cease. 

In  the  spring,  difficulty  is  often  encountered 
in  starting  the  water  through  the  heavy  accumu- 
lation of  snow  in  the  ditch,  which,  if  it  be  long, 
can  be  flushed  out  only  with  great  trouble1. 
This  operation  will  be  materially  hastened  if  the 
ditch  is  cleaned  out  in  short  sections  of  a  mile  or 
two  each.  Cut  a  hole  in  the  bank  a  mile  from 
the  head,  and  when  the  water  has  soaked  that 
far  it  will  carry  off  the  unmelted  snow  through 
this  break  with  great  rapidity.  As  soon  as  clear 
the  hole  is  mended  and  another  made  a  mile 
further  on.  Time  will  be  saved  by  thus  taking 
the  ditch  in  sections. 


H  YDRA  ULIC  MINING.  5  7 

Cost. — When  the  plough  and  scraper  can  be 
used  ditching  can  be  done  at  20  cents  per  cubic 
yard.  If  the  soil  is  so  rocky  as  to  call  for  the 
pick  and  shovel,  it  will  cost  from  30  to  40  cents. 
A  safe  figure  to  be  taken  for  the  construction  of 
a  ditch  3  feet  wide  at  bottom,  4|-  feet  wide  at 
top,  and  18  inches  deep  is  $1.25  per  rod.  It 
can  be  done  for  less.  The  larger  the  ditch  the 
less  costly  it  will  be  in  proportion. 


CHAPTER  VI. 

FLO W  OF   WATER  IN  FLUMES  AND  DITCHES. 

THE  following  rules  for  the  solution  of  prob- 
lems concerning  the  flow  of  water  in  ditches  and 
iiumes  are  commended  to  the  miner,  only  with 
the  proviso  that  the  directions  laid  down  in 
Chapter  V  he  strictly  complied  with.  Before 
doing  any  figuring  let  every  element  of  the  prob- 
lem, as  grade,  area  of  section,  velocity,  wet  peri- 
meter, discharge,  and  length,  be  reduced  from 
the  ordinary  measurements  usually  given  to 
those  laid  down  in  the  "Directions."  If  this  is 
done  the  results  may  be  depended  upon  ;  other- 
wise they  will  be  of  no  value. 

It  is  to  be  remembered,  however,  that  these 
rules  do  not  take  into  account  leakage  and 
evaporation — two  elements  of  loss  which  have 
been  spoken  of  already.  It  will  be  impracticable 
in  this  manual  to  enter  into  the  details  of  these 
elements  of  loss,  as  the  subjects  are  too  intri- 

58 


HYDRAULIC  MINING.  59 

cate ;  and,  in  addition,  it  would  be  unnecessary, 
inasmuch  as  the  records  of  experience  are  more 
satisfactory  and  nearer  the  truth. 

1.  What  grade  per  foot  must  be  given  to  a 
flume  or  ditch  of  uniform  section  to  enable  it  to 
discharge  a  given  quantity  of  water  in  a  given 
time? 

RULE  1.  Divide  the  number  of  cubic  feet  of 
discharge  required  by  the  area  in  square  feet  of 
the  section  of  the  flume.  This  result  is  the 
velocity  necessary,  expressed  in  feet  per  second. 

Multiply  this  result  by  itself. 

Multiply  this  product  by  the  wet  perimeter, 
expressed  in  feet,  and  multiply  this  product  by 
the  decimal  .0001114. 

Divide  this  product  by  the  area  of  the  section 
of  flume,  expressed  in  square  feet.  Call  the  re- 
sult A. 

Multiply  the  velocity  in  feet  per  second  by  the 
wet  perimeter,  expressed  in  feet,  and  multiply 
this  product  by  the  decimal  .00002426. 

Divide  this  product  by  the  area  of  the.  section 
of  the  flume,  expressed  in  square  feet.  Call  the 
quotient  B. 


6O  HYDKA  ULIC  MINING. 

Add  together  A  and  B. 

The  result  is  the  grade  per  foot  (expressed  in 
decimals  of  a  foot)  which  must  be  given  to  the 
flume  to  make  it  carry  the  required  water. 

EXAMPLE. — What  grade  per  foot  of  length 
must  be  given  to  a  20-inch  flume  whose  sides  are 
12  inches  high,  in  order  that  it  may  deliver  28 
cubic  feet  of  water  per  second  steadily  ? 

Wet  perimeter,  say  42  inches    =  3.5  feet. 

Area  of  section,  240  sq.  inches^  1.66  sq.       " 

Discharge,  =28.00  cubic  " 

Then,  dividing  the  discharge  (28)  by  the  area 
of  section  (1.66),  we  have  16.86  as  the  velocity  in 
feet  per  second. 

Following  the  rule,  the  velocity  (16.86)  multi- 
plied by  itself  equals  284.25  ;  multiplying  this 
by  wet  perimeter  (3.5)  produces  994.87 ;  multi- 
plying again  by  the  decimal  .0001114  produces 
.1108  ;  dividing  this  by  urea  of  section  (1.66) 
gives  .0667.  Call  this  A.  Multiplying  the  ve- 
locity (16.86)  by  wet  perimeter  (3.5),  and  the 
product  by  .00002426,  produces  .0014315,  which 
divided  by  the  area  of  the  section  of  the  flume 
(1.66)  =.00086.  Call  this  B.  Adding  A  (.0667) 


HYDRAULIC  MINING.  6 1 

to  B  (.00086),  we  have  as  a  final  result  .06756, 
which  is  the  grade  per  foot  (expressed  in  deci- 
mals of  a  foot).  If  we  multiply  this  result 
(.06756)  by  1,000,  we  have  the  grade  per  thou- 
sand feet,  which  will  be  67.5  feet  (near  enough). 

To  reduce  this  result  to  the  ordinary  terms — 
viz.,  inches  per  box  of  12  feet — divide  first  1,000 
by  12,  which  produces  83.33  (which  of  course 
represents  the  number  of  12-foot  boxes  in  a 
1,000-foot  flume).  Then,  the  grade  being  67.5 
feet  in  83.33  boxes,  for  each  box  it  would  be  the 
result  of  d  viding  67.5  by  83.33,  which  is  .79,  or 
the  grade  would  be  .70  of  a  foot  per  box  of  12 
feet.  Finally,  there  being  12  inclu  ^  in  a  foot, 
we  multiply  .79  by  12  and  obtain  9.48  inches  per 
box,  or  nearly  9^  inches. 

2.  What  is  the  average  velocity  and  discharge 
secured  in  a  flume  or  ditch  of  uniform  cross- 
section  and  grade  ? 

KULE  2.-— Multiply  area  of  cross-section  in 
square  feet  by  the  grade  in  feet  per  foot,  and  the 
product  by  9,000. 

Divide  this  result  by  the  wet  perimeter  in 
feet. 


62  HYDRAULIC  MIMXG. 

Extract  the  square  root  of  the  quotient.  (See 
table  at  end  of  book. ) 

From  the  result  subtract  .1089. 

The  result  equals  the  mean  velocity  of  the 
water  (expressed  in  feet  per  second). 

Multiply  the  area  of  cross-section  by  the  mean 
velocity. 

The  result  equals  the  discharge  (expressed  in 
cubic  feet  per  second). 

EXAMPLE. — What  is  the  discharge  attained  in 
a  30-inch  flume  with  12-inch  sides,  having  a 
uniform  grade  of  f  -*)Tr  (.01)  of  a  foot  for  every 
foot  of  length  ? 

Multiplying  the  area  of  cross-section  (2.5 
square  feet)  by  the  grade  (.01)  produces  .025  ; 
multiplying  this  by  9,000  yields  225  ;  dividing 
this  by  the  wet  perimeter  (4.5)  gives  50,  whose 
square  root  is  7.0711;  subtracting  from  this  the 
decimal  .1089,  we  have  6.9622,  which  is  the  mean 
velocity  (expressed  in  feet  per  second). 

This  calculation  is  in  reality  accurate  only  for 
a  flume.  In  a  ditch,  where  friction  is  greater,  it 
will  be  necessary  to  subtract  about  10  per  cent, 
(or  .6962)  from  the  result  found,  leaving  6.266 


HYDRAULIC  MINING.  63 

as  the  correct  figure.  Then  continuing,  multi- 
ply the  mean  velocity  (6.9622)  by  the  area  of 
cross-section  (2.5)  ;  we  have  17.40,  which  is  the 
discharge  (expressed  in  cubic  feet  per  second). 

3.  What  must  be  the  section  of  a  ditch  or 
Hume  of  uniform  grade  which  will  discharge  a 
given  quantity  of  water  in  a  given  time  ? 

There  is  no  simple  rule  that  will  solve  this 
problem,  and  an  answer  must  be  sought  experi- 
mentally upon  the  following  plan  : 

RULE  3.  Assume  a  convenient  section,  and,  the 
grade  being  known,  calculate  its  discharge  ac- 
cording to  Rule  2,  page  61.  If  this  discharge  is 
greater  or  less  than  the  required  one  try  again 
with  a  smaller  or  larger  section  until  the  correct 
one  is  found. 

Cost. — With  lumber  at  $12  to  $15  per  thou- 
sand, delivered  at  the  head  of  the  flume,  so  that 
it  can  be  floated  down,  a  flume  2£  feet  wide  and 
2J  feet  high  can  be  finished  at  a  cost  of  $3.85 
per  box  (of  12  feet  in  length) ;  and  one  6  feet 
wide  and  3-J-  feet  high  at  $8.50  per  box. 


CHAPTER  VII. 

IRON  PIPING. 

THE  problems  which  arise  in  operating  iron 
pipes  are  the  following : 

1.  What  is  the  velocity  attained  in  a  cylindri- 
cal iron  pipe,  laid  straight  or  with  easy  curves, 
its  head,  length,  and  diameter  being  known? 

BULE  1.  Multiply  the  diameter  in  feet  by  the 
head  in  feet.  Call  this  product  A. 

Add  together  the  total  length  of  pipe  in  feet, 
and  .54  times  its  diameter  in  feet.  Call  this 
sum  B. 

Divide  A  by  B. 

Extract  the  square  root  of  the  quotient  (see 
table  at  end  of  book)  ;  multiply  this  root  by  48. 
The  product  will  be  the  velocity  in  feet  per 
second. 

EXAMPLE. — What  velocity  will  be  attained  in 
a  pipe  12,600  feet  long,  6  inches  (.5  of  a  foot)  in 
diameter,  and  having  a  head  of  200  feet  ? 


// }  DRA  ULIC  MINING.  65 

Multiply  diameter  (.5)  by  head  (200)  =100; 
call  this  product  A.  Add  to  the  total  length 
(12,600  ft.)  54  times  its  diameter:  .5  multiplied 
by  54  equals  27=12,627.  Call  this  sum  B.  Di- 
vide A  (100)  by  B  (12,627)  =.0079.  Extract  the 
square  root  of  this  resulf,  which  =  .0889.  Mul- 
tiply this  root  by  48=4.26,  which  is  the  velocity 
per  second,  in  feet. 

2.  How  many  cubic  feet  of  water  per  second 
will  be  discharged  from  a  cylindrical  iron  pipe, 
straight  or  with  easy  curves,   its  head,  length, 
and  diameter  being  known  ? 

RULE  2.  Ascertain  the  velocity  by  preceding 
rule.  Then  multiply  the  velocity  thus  attained 
by  the  area  in  square  feet  of  a  section  of  the 
pipe.  The  result  will  be  the  discharge  per  sec- 
ond, in  cubic  feet. 

3.  What   head    of  water   is   necessary   for   a 
cylindrical    iron    pipe,    straight    or   with    easy 
curves,  its   diameter  and   length  being  known, 
to  produce  a  given  discharge  per  second  ? 

RULE  3.  Multiply  the  required  discharge 
(expressed  in  cubic  feet)  by  itself.  Call  this 
A. 


66  HYDRAULIC  MINING. 

To  tne  total  length  of  pipe  add  54  times  its 
diameter.  Call  this  B. 

Multiply  A  by  B.     Call  the  product  C. 

Divide  the  diameter  (expressed  in  feet)  by 
.235. 

Multiply  this  product  by  itself  continuously 
four  times. 

Divide  C  by  this  product. 

The  quotient  will  be  the  head  in  feet. 

EXAMPLE. — What  head  is  necessary  to  pro- 
duce a  discharge  of  12  cubic  feet  per  second  at 
the  end  of  a  pipe  8  inches  (.666  feet)  in  diame- 
ter and  350  feet  long,  the  pipe  being  straight 
or  with  easy  curves  ? 

Multiply  the  discharge  (12)  by  itself  =  144; 
call  this  A.  To  the  total  length  (350)  add  54 
times  its  diameter  (36)  =386 ;  call  this  B. 
Multiply  A  (144)  by  B  (386)  =55,584  (C).  Di- 
vide the  diameter  (.666)  by  .235  =  2.834.  Mul- 
tiply this  product  (2.834)  by  itself  continuously 
four  times  =182.801.  Divide  C  (55,584)  by  this 
product  (182.801)  =  3.04  feet  nearly,  which  is  the 
required  head. 

4,   Wliat  diameter  of  pipe  is  necessary  to  carry 


H  YDRA  ULIC  MINING.  67 

a  given  quantity  of  water  per  second,  its  length 
and  total  head  being  known  ? 

RULE  4.  Multiply  the  head  in  feet  by  5,280, 
and  divide  the  product  by  the  length  in  feet. 
Call  this  A. 

Multiply  the  discharge  in  cubic  feet  per  sec- 
ond by  itself,  and  multiply  this  product  by 
5,280.  Call  this  B. 

Divide  B  by  A. 

Extract  the  fifth  root  of  the  result  (see  tables 
at  close  of  book). 

Multiply  this  by  the  decimal  .235. 

The  product  is  the  diameter  (in  feet). 

EXAMPLE. — What  must  be  the  diameter  of  a 
pipe  6,000  ft.  long,  with  a  head  of  400  feet, 
which  will  discharge  G  cubic  feet  of  water  per 
second  ? 

Multiply  the  head  (400)  by  5,280=2,112,000, 
and  divide  this  product  by  the  length  (6,000)  = 
352  (A). 

Multiply  the  discharge  (6)  by  itself  =36,  »nd 
multiply  this  product  by  5,280=190,080  (B). 

Divide  B  (190,080)  by  A  (352)  =540. 

Extract  fifth  root  of  this  quotient  (540)  =3.52. 


68  HYDRAULIC  MINING. 

Multiply  this  root  (3.52)  by  .235  — .8272,  which 
is  the  required  diameter  (expressed  in  decimals 
of  a  foot). 

Curves. — Curves  and  bends  in  pipes  always 
cause  some  loss  of  power.  They  also  furnish  a 
place  for  the  accumulation  of  air  and  sediment, 
as  well  as  weaken  the  tube.  They  are,  how- 
ever, unavoidable  in  practice,  and  the  rules  by 
which  to  calculate  the  additional  amount  of 
head  necessary  to  counteract  their  influence,  or 
the  amount  of  power  lost,  are  perhaps  too  com- 
plex for  the  aim  of  this  work.  An  angular  bend 
in  a  pipe  should  be  avoided,  if  at  all  possible. 
In  most  placer  districts  there  are  workers  of 
sheet-metal  of  sufficient  ability  to  produce  cir- 
cular elbows.  The  latter  should  be  made  with  a 
radius  never  less  than  five  times  the  length  of 
their  diameter.  To  ascertain  this  curve  mea- 
sure the  diameter  of  the  pipe,  and  cut  a  string 
that  will  be  just  five  times  this  length.  Then 
if  one  end  of  the  string  be  held  fast  the  other 
will  describe  the  correct  curve.  A  still  larger 
radius  is  better  when  possible.  In  fact,  the 
gentler  the  curve  the  better. 


HYDRA  UL1C  MINING.  69 

Care  should  be  taken  to  back  up  piping  very 
solidly  at  each  change  of  direction.  The  neces- 
sity of  this  precaution  will  be  self-evident. 
Cases  have  occurred  where  whole  sections  of 
piping  poorly  backed  have  been  torn  to  pieces 
as  soon  as  the  head  was  put  on. 

The  cost  of  piping,  finished  and  set  up,  may 
be  approximated  as  follows  : 

Cost  at  manufactory 4^c.  per  Ib. 

Freight,  1,500  miles 3^c. 

Making  into  pipe 3£c.        " 

Grading,  laying,  ballasting,  and  fas- 
tening      £,c.       " 

12c.  per  Ib. 

The  hydraulic  grade-line  is  an  imaginary 
straight  line,  extending  from  a  point  on  the 
side  of  the  water-box  or  reservoir,  denominated 
the  velocity-head,  to  the  mouth  of  the  nozzle. 
If  the  pipe  be  constructed  exactly  on  this  line, 
the  water  flowing  through  it,  no  matter  what  its 
velocity  or  volume,  will  exert  no  bursting  pres- 
sure. In  other  words,  the  grade  of  the  hydraulic 
grade  line  is  such  that  the  velocity  caused  by  the 
grade  is  exactly  sufficient  to  carry  down  all  that 


70  HYDRAULIC  MINING. 

'the  pipe  will  hold,  and  there  is  no  outward  pres- 
sure exerted  except  that  on  the  bottom  of  the 
pipe  due  to  the  water's  weight.  If,  however, 
there  he  a  change  in  the  diameter  of  the  pipe  at 
any  point  this  equilibrium  ceases  to  exist.  It  is 
never  possible  in  practice  to  adopt  this  line  as  a 
course,  but  generally  close  approximations  can 
be  made  to  it.  As  will  be  shown  further  on,  it  is 
highly  advantageous  to  do  this  wherever  possible. 

To  find  the  Hydraulic  Grade-Line. — RULE  1. 
Calculate  the  velocity  in  pipe  due  to  the  total 
head.  (See  Rule  1,  page  64.) 

Look  in  Table  3,  and  find  the  head  correspond- 
ing to  this  velocity. 

Lay  off  this  head  on  the  side  of  the  reservoir 
from  the  surface  of  the  water.  Its  termina- 
tion will  mark  the  line  of  the  velocity-head. 
From  this  point  sight  to  the  nozzle  of  the  pipe  ; 
the  line  of  sight  is  the  hydraulic  grade-line. 

In  constructing  a  line  of  piping  three  cases 
may  arise  by  reason  of  the  inequalities  of  the 
ground  to  be  passed  over  : 

1.  The  pipe  may  lie  below  the  hydraulic  grade- 
line. 


// 1  'DRA I  'LIC  MIKING.  7  I 

3.  T,he  pipe  may  lie  above  the  hydraulic  grade- 
line. 

3.  The  pipe  may  lie  both  above  and  below. 

CASE  1.  Pipe  below  Hydraulic  Grade- Line. — 
There  is  here  a  bursting  pressure,  varying  in 
amount  according  to  its  distance  below  the  line. 
To  find  this  pressure  at  any  point,  ascertain  the 
distance  of  that  point  vertically  below  the  hy- 
draulic grade-line.  Call  this  measurement  the 
bursting-head — as,  for  example,  A,  E,  Fig.  1, 
which  assume  to  be  6  feet.  The  pressure,  then, 
on  each  square  inch  of  pipe  at  that  point  is  equal 
to  the  weight  of  a  column  of  water  whose  base 
measures  1  square  inch  and  whose  height  is 
6  feet.  Thus,  1  square  inch  multiplied  by  6  feet 
(72  inches)  =72  cubic  inches  =.04166  cubic 
feet  multiplied  by  62.5  (wt.  of  cubic  foot  of 
water)  =2. 6  Ibs.,  which  is  the  pressure  per 
square  inch.  Consequently,  if  the  pipe  lies  con- 
siderably below  the  hydraulic  grade-line,  it  will 
need  to  be  of  thicker  iron  than  the  rest.  This 
law  applies  in  crossing  deep  hollows. 

CASE  2.  Pipe  above  the  Hydraulic  Line. — 
There  is  now  a  decided  loss  of  head,  and  conse- 


72  H\DRAULIC  MINING. 

quently  of  power,  in  portions  of  the  pipe,  if  it  be 
of  the  same  diameter  throughout.  Find  now 
that  point  in  the  pipe  which  is  highest  above 
the  -hydraulic  grade-line  (H),  and  from  that 
point  draw  Uo  new  grade  lines,  one  to  the 
pressure -box  (H  V)  and  one  to  the  nozzle  (H 
N).  Along  the  former  calculate  the  bursting 
pressure  as  above,  measuring  the  different  heads 
from  the  new  line  (as  F  E).  Along  the  latter 
there  will  be  no  bursting  pressure,  for  the  grade 
of  the  nozzle  end  of  the  pipe  will  be  so  much 
greater  than  that  of  the  reservoir  end  that  it  will 
carry  off  the  water  very  much  faster,  and  will,  in 
fact,  act  like  a  gutter,  and  be  partially  empty. 
The  remedy  for  this  is  to  put  in  pipes  having  a 
decreased  diameter.  To  calculate  the  requisite 
diameter,  assume  that  the  pipe  ended  at  that 
point  where  it  is  highest  above  the  hydraulic 
grade-line  (H).  Calculate  the  discharge  in  cubic 
feet  at  that  point  according  to  Rule  2,  page  (55. 
This  will  give  the  amount  of  water  in  cubic  feet 
per  second  which  the  nozzle  section  (H  N)  must 
carry.  The  head  will  be  the  vertical  distance 
from  H  to  N.  Then,  by  Rule  4,  under  the  head 


H  YDRA  UL1C  MINING.  J  3 

of  Iron  Piping,  the  requisite  diameter  may  be 
calculated. 

CASE  3.  Pipe  both  above  and  below  the  Hy- 
draulic Grade- Line. — The  problem  now  becomes 
more  complicated. 

Divide  the  pipe  into  sections  for  every  passage 
it  makes  above  the  hydraulic  grade-line,  and 
make  the  divisions  at  the  several  points  (A,  H, 
and  I)  where  the  pipe  attains  its  highest  posi- 
tion. Calculate  (Rule  2,  page  61)  the  discharge 
at  the  end  of  each  section.  The  first  section 
will  have  a  head  equal  to  the  vertical  distance 
between  its  discharge  and  the  velocity-head  in 
the  pressure-box.  All  succeeding  heads  will  be 
measured  from  the  level  of  the  discharge  just 
below  them  to  their  own  discharge.  For  ex- 
ample, the  head  at  A  is  the  vertical  distance 
between  A  and  the  water-level  in  the  reservoir, 
less  the  velocity-head.  At  H  the  head  is  the  ver- 
tical distance  between  H  and  A.  At  I  it  is  the 
distance  between  I  and  H,  etc.  These  measure- 
ments will  furnish  a  series  of  heads  and  grades 
from  which  the  diameters  of  pipe  necessary  may 
be  calculated  according  to  Rule  4,  p.  66. 


74  HYDRA  ULIC  MINING. 

If  it  be  desired  to  calculate  bursting  pressure 
in  Case  3,  measure  the  heads  of  different  points 
from  the  ne \v  hydraulic  grade-lines,  and  proceed 
as  directed  in  Case  1. 

In  building  and  laying  lines  of  iron  piping, 
whether  to  conduct  water  from  one  reservoir  to 
another  or  from  the  water-box  to  the  pit,  money 
will  be  saved  by  paying  close  attention  to  this 
subject.  It  will  easily  be  seen  that  if  the  pipes 
are  larger  than  is  necessary,  iron,  which  is  gene- 
rally costly  in  mining  communities,  will  be  un- 
necessarily used,  while  at  the  same  time  the 
pipes  will  become  filled  with  air,  and  much  of 
the  force  thereby  lost.  Again,  if  the  pipes  are 
too  small,  the  danger  from  bursting  is  greatly 
augmented. 

The  pipe,  after  being  laid,  should  be  carefully 
anchored  at  many  points,  and,  when  possible, 
protected  from  the  weather. 

The  three  conditions  arising  under  unequal 
and  varying  grades  are  shown  by  the  following 
figures : 


HYDRA  ULIC  MINING  7  5 

Fig.  1. — Pipe  below  Hydraulic  Grade- Line. 
Fig.1. 


W.- Water-box.    F.  E.  N.— Line  of  Pipe.     V.  A.  N.— Hydraulic 
Grade-Line.      A.  E.—  Bursting-head. 

Fig.  2. — Pipe  above  Hydraulic  Grade- Line. 
Fig.  2. 


W.— Water-box.  E.  H.  N.— Piping.  V.  N.-Hydraulic  Grade-Line. 
F.  E.— Bursting-head.  V.  H.  and  H.  N.— Supplementary  Hy- 
draulic Grade-Lines. 

Fig.  3. — Pipe  above  and  beloiv  Hydraulic  Grade" 
Line. 
Fig.3. 


W.-Water-box.  A.  E  H.  F.  I.  N.-Piping.  V.  N.-Hydraulic 
Grade-Line.  V  A,  A  H,  H  I.  I  N— Supplementary  Hydraulic 
Grade-Lines. 


76 


HYDRA  ULIC  MINING. 


Sheet  iron,  from  which  the  piping  is  made,  is 
manufactured  of  various  thicknesses.  The  stan- 
dard of  measurement  is  the  inch,  and  a  size 
known,  for  example,  as  No.  16  is  approximately 
^  of  an  inch  in  thickness.  The  following  table 
will  give  the  strength  of  sheet-iron  piping,  and 
will  be  found  of  service. 

STRENGTH    OF    IROtf    PIPING. 

This  table  gives  the  thickness  In  Inches  and  decimals  of  an  Inch 
which  Iron  piping  must  have  to  stand  a  given  pressure. 


«                                        Heud  of  Water,  in  feet. 

I     - 

150 

200       250       300  :    400      500 

600        800 

1,000 

(£;        Resulting  Pressure  against  Sides  of  Pipe,  i:i  Its.  per  sq 

^ 

inch. 

|     '  48-4 

65.1 

87    |    109       130       174      217 

260        347 

434 

Q      ]  Required  I  hick  ness  of  Pipe,  in  in  ches  or  decimci  Is  of  an 

inch. 

2      j   .009 

.013 

.018      .022      .027      .036  !    .045 

.055       .075 

.095 

8         .013 

.020 

026      .033      .040      .054  !    .068 

.082       .112 

.143 

4         .017 

.026 

.035      .045      .053      .072      .090 

.110  ,     .149 

.191 

5      ;   .022 

.033 

.044      .056      .067      .090  ,    .113 

.137        .186 

.237 

6         .026 

.040 

.053      .067      .080      .'08      .136 

.165       .224 

.287 

7         .030 

.046 

.062      .078      .093      .126  j    .159 

.193       .261 

.333 

8      !   .034 

.053 

.071      .089      .107      .144      .181 

.220       .298 

.382 

9          .039 

.059 

.079      .101      .120      .163  j    .205 

.247        .335 

.427 

10          .044 

.1166 

.089      .112      .134      .181      .227 

.275        .373 

.475 

12       i   .053 

.080 

.106      .134      .161      .217  i    573 

.330       .448 

.575 

14          .061 

.093 

.124      .156      .187      .253  i    .318 

.387        .523 

.666 

16      j    .069 

.106 

.142      .178      .214      .288      .363 

.440  i     .596 

.763 

18      \  .078 

.120 

.159      .201      .242      .326  1    .409 

.495        .670 

.850 

20      !    .088 

.132 

.177      .223      .267      .361  ;    .454 

.549        .746 

.950 

24          .105 

.159 

.2i3      .268      .321      .433  i    .545 

.660        .895 

l.iro 

30          .132 

.198 

.267      .336      .402      .543       .681 

.825      1.120 

1.4J) 

36          .156 

.238 

.318      .402      .483      .651  ,    .8  9 

.990  !    1-340 

1710 

42       i   .184 

.279 

.372      .469      .562      .759       .955 

1.160  j    1.570 

2.000 

48      ;   .210 

.317 

.425      .535      .641      .866     1.090 

1320      1.790 

2.290 

HYDRAULIC  MINING.  fj 

For  example  :  What  thickness  of  iron  should 
be  used  to  make  a  20-inch  pipe  which  must 
bear  200  feet  head  of  water  ?  The  figure  given 
in  the  table  is  .17?  inch,  which,  by  the  follow- 
ing table,  corresponds  to  between  No.  5  and  No. 
6  iron.  Or,  the  head  being  100  feet  and  the 
pipe  10  inches  in  diameter,  the  thickness  will  be 
.044  inches,  which  corresponds  nearly  to  No.  17. 
In  selecting  the  iron  it  will  always  be  safer  to 
take  the  size  one  larger  than  that  called  for  by 
the  figures. 

Table  showing  the  thickness,  in  decimals  of 
an  inch,  of  the  different  sizes  of  sheet-iron  from 
No.  4  up  to  No.  30  : 

No.     4  has  a  thickness  of  .204  of  an  inch. 
;<      5         «         "          "   .181     " 
"      6        "        "          "   .162     " 


9  u  «  «  114 

10  u  "  "  .101 

11  "  <(  "  .090 

12  "  "  '«  .080 

13  "  "  l<  .071 

14  »•  "  "  .064 

15  '•'  "  "  .057 

16  "  '«  •«  .050 


HYDRA  ULIC  MINING. 


No.  17  has  a  thickness  of  .045  of  an  inch. 


18 

"  .040  " 

19 

"  .035  " 

20    "    « 

"  .031  " 

21 

"  .028  " 

22 

"  .025  " 

23 

"  .022  " 

25 

u  .020  "    ' 
<«  017  « 

26 

"  .015  " 

27 

"  .014  " 

28 

"  .012  " 

29 

"  .011  " 

30 

"  .010  " 

It  must  be  remembered  that  tlicse  figures  ap- 
ply only  in  cases  where  the  end  of  the  pipe  is 
closed  and  no  discharge  occurs,  or  where  the 
discharge  is  on  the  same  level  as  the  inflow.  Of 
course  if  the  pipe  is  discharging  at  one  end  the 
pressure  is  relieved,  and  the  pipe  is  called  upon 
to  sustain  only  that  bursting  pressure  due  to  its 
depression  below  the  hydraulic  grade-line.  As 
in  practice  the  depression  of  the  pipe  leading 
from  the  water-box  to  the  pit  is  rarely  more  than 
5  to  20  feet  below  the  hydraulic  grade-line,  the 
iron  will  be  compelled  to  resist  a  pressure  never 
over  10  Ibs.  to  the  square  inch.  This,  ordinary 
stove-pipe  iron  would  generally  do. 


CHAPTER  VIII. 

NOZZLES  AND  DISCHARGE. 

THEORETICALLY,  the  quantity  of  water  dis- 
charged from  the  nozzle  of  a  pipe  may  be  de- 
termined by  the  following  rule: 

KULE  1.  Extract  the  square  root  of  the  head, 
and  multiply  this  root  by  8.03.  The  product 
will  be  the  velocity  in  feet  per  second  with 
which  the  water  escapes  from  the  mouth-piece. 

Multiply  the  area  of  the  mouth-piece  (see- 
page 41)  by  this  velocity,  and  the  result  will  be 
the  discharge  in  cubic  feet  per  second. 

EXAMPLE. — What  quantity  of  water  will  be 
discharged  from  a  pipe,  under  a  head  of  100 
feet,  through  a  3-inch  nozzle  ? 

The  square-root  of  the  head  (100)  is  10, 
which,  multiplied  by  8.03,  gives  80.3  feet  as 
tin-  velocity  per  second.  The  diameter  of  nozzle 


8O  H YDRA  ULIC  Mh\  ING. 

being  3  inches  (.25  of  a  foot),  its  area  would 
be  .25  multiplied  by  3.14  multiplied  by  .0625  = 
.04906  square  feet,  which,  multiplied  by  the  ve- 
locity 80.3,  equals  3.93  cubic  feet,  which  is  the 
discharge  per  second. 

The  actual  discharge  is  probably  about  80  per 
cent,  of  the  theoretical  one  in  well-made  nozzles, 
provided  with  inside  flanges  to  prevent  revolu- 
tion of  the  stream,  and  in  this  case  would  be 
3.14  cubic  feet  per  second. 

This,  reduced  to  miners'  measure  (see  page  18), 
would  represent  about  115  inches.  The  power 
of  the  stream  thrown  by  a  nozzle  has  been  dis 
cussed  under  the  head  of  Momentum  (page  39), 
and  nothing  remains  to  be  said  on  the  subject, 
except  that  every  precaution  should  be  taken  to 
prevent  the  stream  from  issuing  in  a  ragged  con  • 
dition.  Its  effectiveness  depends  very  largely 
upon  its  smooth  and  cylindrical  form.  If  this 
is  secured  it  will  travel  through  the  air  for 
a  much  longer  distance  without  disintegration 
than  otherwise.  The  mouth-piece,  therefore, 
should  be  very  smooth,  and  the  arrangements 
of  the  pressure  or  water  box  so  perfect  as  to 


H  YDRA  ULIC  MINING.  8 1 

exclude  all  sand  and  gravel,  and,  if  possible,  all 
air.  Fine  specks  of  quartz  passing  through  the 
mouth-piece  will  not  onlv  cut  the  metal,  but  will 
spoil  the  shape  oi  tne  jet. 


CHAPTER  XX. 

THE  SLUICE. 

UPON  the  construction  and  operation  of  these 
channels  almost  everything  in  placer-mining  de- 
pends.    It  is  a  comparatively  simple  matter  to 
disintegrate  the  most  cohesive  gravel-bank  and 
deliver  it  at  the  head -box,  but  by  no  means  so 
easy  to  so  conduct  the  washing  as  to  save  even  a 
respectable  amount  of   gold.      In   former   days 
miners  were  content  with  saving  from  30  to  50 
per  cent.,  for  the  ground  worked  at  those  times 
was  rich  enough  to  pay  handsomely  even  then. 
The  miner  of  to-day,  however,  has  to  deal  with 
a  lower  grade  of  material   worth  from  15  to  25 
cents  to  the  cubic  yard,  and  must  work  closer  to 
produce  a  profit.      In  California  ground  worth 
only  4  cents  to  the  cubic  yard  is  worked  suc- 
cessfully.    In  Colorado  and  Montana  there  is  no 
need  as  yet  (and  in  fact  there  is  none  in  Cali- 
fornia) to  touch  such  poor  gravel,  for  there  are 


HYDRAULIC  MINING.  83 

millions  of  acres  still  unopened  which  will  pro- 
duce 20  to  30  cents.  This  circumstance,  how- 
ever, affords  no  legitimate  excuse  for  careless 
working.  It  will  be  found  at  the  present  day 
to  be  just  as  expensive  to  save  50  as  90  per  cent, 
in  mines  where  there  is  any  pretence  to  careful 
work.  And  the  sooner  the  business  of  gravel- 
washing  is  reduced  to  a  science,  the  sooner  it 
will  attract  the  attention  of  investors  and  re- 
ceive the  benefit  of  their  assistance. 

Steadiness  of  flow  in  a  sluice  is  of  great  im- 
portance. The  quantity  of  water  passing,  and 
its  velocity,  must  be  uniform  to  secure  the  de- 
position of  a  maximum  of  gold.  Again,  it  is  no 
economy  to  crowd  a  flume  with  dirt  beyond  cer- 
tain limits,  which  will  be  noted  further  on.  If 
the  gravel  is  caved  in  too  large  quantities  it  will 
be  found  economical  to  erect  other  sluices.  It  is 
to  be  remembered,  also,  that  water  always  tra- 
vels faster  in  the  centre  of  the  channel,  and  is 
also  higher  in  level.  Consequently  the  bulk  of 
the  gravel  and  boulders  will  travel  down  the 
middle  of  the  flume. 

Dimensions — The  maximum  quantity  of  wa- 


84  HYDRAULIC  MINING. 

ter  which  may  be  advantageously  used  in  a  sin- 
gle sluice  of  correct  dimensions  when  the  ground 
is  ordinarily  full  of  boulders,  is  set  down  by  good 
practical  authorities  at  1,000  miners'  inches. 
This  corresponds  to  a  discharge  of  95,000  cubic 
feet  per  hour,  which,  with  gravel  and  boulders, 
would  represent  about  double  that  amount  of 
moving  substance  in  the  sluice.  When  more 
than  this  is  used  the  current  will  be  so  strong 
that  men  cannot  work  to  any  advantage  in  the 
head-box.  Sluices  intended  to  clear  off  top  dirt 
must  be  short  and  large.  In  this  case  the  top 
dirt  is  presumed  to  be  nearly  free  of  gold  and 
of  boulders. 

The  test  of  friction  is  perhaps  the  correct  one 
on  which  to  base  calculations  for  the  correct  di- 
mensions. The  general  behavior  of  this  force 
is  referred  to  on  page  38,  and  on  page  52  will  be 
found  the  law  of  the  least  wet  perimeter.  In  a 
sluice,  the  object  being  to  move  all  the  gravel 
from  the  head-box  to  the  dump  by  means  of  the 
forces  of  water  and  gravity,  it  is  important  that 
the  least  amount  of  the  former  should  be  lost  in 
overcoming  extraneous  resistance.  We  may  in- 


HYDRAULIC  MINING.  85 

crease  the  work  of  the  water  by  giving  it  veloci- 
ty through  the  instrumentality  of  heavy  grade, 
but  if  the  flume  is  of  incorrect  dimensions  there 
is  always  a  loss  for  which  the  miner  receives  no 
compensation,  and  which  may  be  avoided. 

To  secure  this  point  let  the  miner  first  decide 
upon  the  largest  sized  boulder  which  he  will 
allow  to  go  through  his  flume.  Tf  it  be  2  feet 
in  diameter,  then  it  is  clear  that  his  flume  must 
carry  at  least  2  feet  in  depth  of  water.  We 
have  then  a  figure  for  a  side  measurement.  Ac- 
cording to  the  law  on  page  52  the  bottom  should 
be  from  If  to  2|  times  the  height  of  the  side,  or, 
taking  the  side  at  30  inches,  the  bottom  should 
be  52J  to  67J  inches  wide.  If,  however,  the 
ground  is  free  from  large  boulders,  and  it  be 
merely  necessary  to  ascertain  the  dimensions 
best  adapled  to  carry  the  greatest  economical 
quantity  of  water  (1,000  inches),  Eules  2  and  3, 
on  pages  41  and  42,  will  furnish  the  correct  area 
of  section.  1,000  inches  is  equal  to  27.1  cubic 
feet  per  second.  Double  this  discharge  to  make 
room  for  the  gravel.  The  flume  must  then  dis- 
charge 54.2  cubic  feet  of  material  per  second. 


86  HYDRAULIC  MINING. 

Having  ascertained  the  area  of  section  in  square 
feet,  we  may  resolve  it  into  correct  dimensions 
by  the  following  rules  : 

RULE  1.  The  width  to  be  2J  times  the  sides. 

Multiply  the  area  in  square  inches  by  4,  and 
divide  the  product  by  9.  Extract  the  square 
root  of  the  quotient.  The  result  will  be  the 
height  of  side  in  inches. 

RULE  2.  The  width  to  be  1J  times  the  sides. 

Multipl}  the  area  in  square  inches  by  4,  and 
divide  the  product  by  7.  Extract  the  square 
root  of  the  quotient.  The  result  will  be  the 
height  of  side  in  inches. 

Those  who  have  a  preference  for  shallow  boxes 
will  adopt  Rule  1,  and  those  who  incline  towards 
deep  ones  will  take  Rule  2. 

Grade. — Grade  creates  velocity.  Velocity  in- 
creases the  work  of  water,  and  consequently 
where  the  quantity,  of  water  is  small  it  must  be 
assisted  by  giving  it  a  greater  velocity.  As  practi- 
cally the  whole  question  of  power  with  water  in 
sluices  depends  upon  the  velocity  with  which  it 
moves,  the  question  of  grade  is  of  great  impor- 
tance. The  miner,  however,  does 'not  merely 


HYDRAULIC  MINING.  8/ 

seek  for  power  in  his  sluice.  While  there  are 
boulders  and  gravel  to  wash  away  there  is  gold 
to  be  saved.  Consequently,  that  velocity  is  the 
best  which  will  wash  away  a  maximum  quantity 
of  gravel  and  rock  and  a  minimum  of  gold.  Let 
the  miner,  therefore,  study  for  a  while  the  com- 
position of  his  banks. 

If  the  boulders  are  rounded  and  well  worn 
they  will  roll  down  the  sluice  with  ease  under  a 
small  head,  but  if  flat  they  will  need  more  power. 
And  the  same  is  true  if  they  be  angular,  though 
not  to  so  great  an  extent. 

Scale  and  leaf  gold  will  float  a  long  distance 
in  a  turbid  and  rapid  stream. 

Generally  the  physical  quality  of  gold  may  be 
determined  by  an  examination  of  the  gravel. 
The  miner  should  not  trust  to  that  caught  in  his 
riffles,  for  much  may  be  washed  away  which  he 
can  never  examine.  If  the  gravel  and  boulders 
are  angular  and  large  the  gold  will  have  the 
same  characteristics  ;  but  if  the  former  are  pol- 
ished the  gold  is  round  or  leafy,  and  much  will 
be  a  fine  dust. 

The  moving  power  of  water  in  sluiceways  may 


88  HYDRAULIC  MINING. 

be     approximately    judged     by    the     following 
table : 

16  feet  per  minute  begins  to  wear  away  fine  clay. 

30  "  «  just  lifts  fine  sand. 

39  "  '  lifts  sand  as  coarse  as  linseed. 

45  "  '  moves  find  gravel. 

120  "  '  "      inch  pebbles.    -      .J 

200  t(  '  "      pebbles  as  large  as  eggs. 

320  "  '  "      boulders  3  to    4  inches  thick. 

400  "  '  "  6  to    8 

600  "  «  "  "      12  to  18  « 

We  have,  then,  the  following  rule  for  the  es- 
tablishment of  grades  in  sluices  when  the  veloc- 
ity needed  is  decided  upon : 

RULE  3. — Multiply  the  velocity  expressed  in 
feet  per  secomi  by  itself,  and  the  product  by 
the  wet  perimeter  in  feet. 

Divide  this  result  by  twice  the  area  in  square 
feet.  The  result  is  the  total  fall  in  feet  per 
mile. 

EXAMPLE. — What  grade  must  be  given  to  a 
sluice  12  inches  broad  and  6  inches  deep,  that  it 
may  carry  a  velocity  of  320  feet  per  minute, 
or  5.3  feet  per  second  ? 

Multiplying  the  velocity  (5.3)  by  itself,  and 


HYDRAULIC  MINING.  89 

the  product  by  the  wet  perimeter  (24  inches  =2 
feet),  we  have  56.18.  This,  divided  by  the  area 
(72  square  inches  =.5  of  a  foot),  and  doubled 
=56.18,  which  is  the  fall  in  feet  per  mile. 

To  reduce  grades  expressed  in  feet  per  mile 
to  inches  per  box  of  12  feet,  multiply  by  the 
decimal  .027.  Thus,  a  grade  of  56.18  feet  per 
mile  equals  a  grade  of  1.5,  or  1£,  inches  per 
box.  To  reduce  to  inches  per  rod  (16  feet), 
multiply  by  the  decimal  .036. 

Prof.  Silliman's  calculations  on  California 
cement  gravel,  after  being  disintegrated  by 
blasting,  indicate  that  1?-|-  cubic  yards  of  wa- 
ter, equal  to  nearly  15  tons,  are  necessary  to 
wash  1  cubic  yard  of  gravel.  For  ordinary 
gravel,  after  being  caved,  probably  8  to  12 
tons  would  suffice. 

When  the  course  of  the  sluice  is  curved  the 
outer  edge  must  be  raised,  to  prevent  unequal 
wear  and  an  accumulation  of  material.  This 
is  much  more  imperative  in  the  sluice'  than  in 
the  flume. 

Riffles. — It  is  not  possible  within  the  limits 
of  this  work  to  discuss  the  subject  of  riffles 


QO  HYDRAULIC  MINING. 

thoroughly.  Nor  is  it  yet  decided  which  of 
the  systems  (wood,  boulder,  or  railroad  iron) 
presents  the  most  advantages  in  the  majority 
of  cases.  The  first  is  the  most  extensively 
used,  and  will  probably  always  hold  its  place. 
Some  experiments  made  in  California  witli 
railroad  iron  demonstrate  that  that  style  of 
riffle  was  strongly  to  be  recommended  for  very 
rocky  ground  at  least.  The  great  efficacy  of 
boulder  riffles  is  well  known,  and  is  thorough- 
ly illustrated  in  the  ground-sluice. 

As  already  stated,  the  bulk  of  gravel  and 
boulders  travels  down  the  centre  of  a  sluice, 
where  there  is  at  once  the  most  water  and 
the  greatest  velocity.  Consequently,  it  will  be 
found  advantageous  to  have  the  riffles  higher 
in  the  centre  than  in  the  sides.  This  will 
cause  a  distribution  of  deposit  over  the  en- 
tire width  of  box,  and  will  also  prevent  the 
formation  of  a  channel  of  depression  in  the 
bottom  of  the  sluice. 

The  cost  of  wooden  block-riffles,  cut  from 
peeled  round  lumber  and  squared,  will  average 
about  $50  per  1,000.  A  thousand  of  these 


HYDRAULIC  MIXIXG.  gi 

blocks  averaging  about  8  inches  diameter  will 
cover  80  square  yards  of  bottom.  Laying  and 
fastening,  and  all  other  expenses  concurrent  with 
arranging  the  bottom  of  the  sluice  for  work,  will 
bring  the  total  cost  to  75  cents  per  square  yard. 
It  will  be  impossible  to  quote  the  expense  of  rail- 
road-iron riffles.  Old  irons  are,  of  course,  just 
as  good  as  new.  The  cost  will  be  mainly  that  of 
transportation. 


92 


H  YDRA  ULIC  MINING. 


TABLE    I. 


TABLE  OF  SQUARE  KOOTS. 


The  following  table  of  the  square  roots  of  numbers  from  1  to  200,  in 
elusive,  will  probably  answer  all  requirements  of  problems  proposed 
in  the  preceding  examples.  If  the  iigure  whose  root  is  to  be  extracted 
is  not  found  in  the  table,  take  the  root  of  the  figure  nearest  to  it. 
For  example,  if  it  is  necessary  to  extract  the  root  of  132.6,  take  the 
root  of  133. 


.Yb.i   Root.      No.     Root, 


11.8823 

11.8743 

11.9164 

11.9583       183 

12.  184 

12.0416  II  185 

12.0830 

12.1244 

12.1655 

I2.30M 

12.2474 


HYDRAULIC  MINING. 


93 


TABLE  II. 

FIFTH     BOOTS. 

The  following  table  of  numbers  and  roots  will  cover  all  problems 
that  come  to  the  miner.  The  numbers  are  printed  in  heavy  type  and 
the  roots  in  light.  If  the  exact  number  is  not  found,  take  the  roots  of 
the  number  nearest  to  it : 


No. 

Root. 

No. 

Root. 

No. 

Root. 

7.59 

1.5 

5032.84 

5.5      59049. 

9. 

32. 

2. 

7776. 

6.   I   77378. 

9.5 

97.65 

2.5 

11603. 

6.5 

100000. 

10. 

243. 

3. 

16807. 

7. 

136638. 

10.5 

525.21 

3.5 

28730. 

7.5 

161051. 

11. 

1024. 

4. 

32768. 

8. 

201035. 

11.5 

1845.28 

4.5 

44370. 

8.5 

248832, 

12. 

3125. 

5. 

94  7/i  'DRA  UL1C  MINING . 

TABLE  III. 

VELOCITIES   AND    DISCHAKGES. 


Head  in  feet 
per  100  feet. 

1 

£fc 

Ci 

1 

DixfJairqe  in  cu. 
j  ft.  per  24  hours. 

.0019 

.0038 

.1 
.2 

.208 
.293 

.1633 
.2301 

14,114 

19.880 

.0057 

.3 

.359 

.2819 

24,360 

.0076 

.4 

.415 

.3267 

28,229 

.095 

.5        .464 

.3638 

31,435 

.0114 

.6 

.508      .3989 

34,464 

.0132        .7 

.549      .4311 

37,427 

.0151 

.8        .585      .4602 

39,760 

.0170 

.9        .623      .4901 

42,343 

.0189 

1.1 

.656      .5144 

44,431 

.0237 

1.25       .735      .5753 

49,701 

.0284       1.50       .805      .6322 

54,604 

.0331       1.75       .871      .6832 

59,011 

.0379 

2. 

.928      .7276 

62,870 

.0426       2.25 

984      .7696 

66,484 

.0473 

2.50 

1.040      .8168  !    7U,'572 

.0521 

2.75 

1.080   !    .8482      73,284 

.0568 

3.00 

1.130      .8914      76,982 

;0758 

4. 

1.310 

1.028 

88,862 

.0947 

5. 

1.47 

1.150 

99,403 

.1136 

6. 

1  61 

1.264 

109,209 

.1325 

7 

1.74 

1.366 

1  18,022 

.1514 

8. 

1.86 

1.455      125,740 

.1703 

9. 

1.96 

1.539 

132,969 

.1894 

10. 

2.08 

1.633 

141,145 

.2273     !  12. 

2.27 

1.782      153,964 

.2J52      14. 

2.45 

1.924      166,283 

.3030      16. 

2.62 

2.057      177,724 

.3409 

18. 

2.78 

2.183 

188,611 

.3788 

20. 

2.93 

2.301 

198,806 

.4735 

25. 

3.28 

2.573 

222,150 

.5682 

30. 

3.59 

2.819 

243,604 

.6629 

35. 

3.88 

3.047 

268,960 

.7576 

40. 

4.15 

3.21)7 

282,288 

.8523 

45. 

440 

3.451 

298,209 

.9470 

50. 

4.64 

3.638 

314,352 

95 


TABLE  III.— Continued. 

VELOCITIES    AND    DISCHARGES. 


Head  in  feet 
per  100  feet. 

jjj 

i1! 

•2  ^ 
^  a. 

Discharge  in  cu. 
ft.  per  24  hours. 

|& 

pi 

I"1 

1.1360 

60. 

5.08 

3.989 

344,649 

1.3260 

70. 

5.49 

4.311 

372,470 

1.5150 

80. 

5.85 

4.602                 397,613 

1.7040 

90. 

6.23 

4.900                  423,435 

1.8940 

100. 

6.56 

5.144 

444,312 

2.0830 

110. 

6.87 

5.395 

466,138 

2.2720 

120. 

7.18 

5.639 

487,209 

2.4620 

130. 

7.47 

5.866 

506,822 

2.8410 

150. 

8.05 

6.322 

546.048 

3.0300 

160. 

8.30 

6.534 

564,576 

3.2190 

170. 

8.55 

6.715 

580,176 

3.4080 

180. 

8.80 

6.903 

596,418 

3.5960 

190. 

9.04 

7.100 

613,440 

3.7880 

200. 

9.28 

7.276 

628,704 

4.2610 

225. 

9.84 

7.696 

664,848 

4.7350 

250. 

10.40 

8168 

705,728 

5.2080 

275. 

10.8 

8.482 

732,844 

5.6820 

300. 

11.3 

8.914 

769,824 

6.6290 

350. 

12.3 

9.621 

831,168 

7.5760 

400. 

13.1 

10.280 

888,624 

8.5320 

450. 

13.9 

10.910 

943,056 

9.4700 

500. 

14.7 

11.50 

994,032 

10.4100 

550. 

15.4 

12.09 

1,044,576 

11.3600 

600. 

16.1 

12.64 

1,092,096 

12.3000 

650. 

16.7 

13.11 

1,132,704 

13.2500 

700. 

17.4 

13.66 

1,180,224 

14.2000 

750. 

18. 

14.13 

1,220,832 

15.1500 

800. 

18.6 

14.55 

1,257,408 

16.0900 

850. 

19.1 

15.00 

1,296,000 

17.0-100 

000. 

19.6 

15.39 

1,329,696 

17.99CO 

950. 

20.3 

15.94 

1,377,216 

18.9400 

1000. 

20.8 

16.33 

1,411,456 

2;>.7£00 

1290. 

22.7 

17.82 

1,539,648 

26.5200 

1400. 

24.5 

19.24 

1,062,336 

30.3009 

1600. 

26.2 

20.57 

1,777,248 

37.8700 

2000. 

29.3 

23.01 

1,988,064 

The  Standard  Wcrfc  dn  the  Subject. 

FIFTH  EDITION. 

One  Volume,  Small  Quarto,  31 3  Pages,  72  Illustrations,  $5.00. 

A  PRACTICAL  TREATISE  ON 

Hydraulic  Mining  in  California, 

With  Description  of  the   Use  and  Construction 

of  Ditches,   Flumes,     Wrought-Iron   Pipes, 

and  Dams:  Flow  of  Water  on  Heavy 

Grades,  and  its  Applicability,  under 

High  Pressure,  to  Mining. 

BY  AUG.  J.   BOWIE,  JR.,  MINING  ENGINEER. 

CONTENTS. 
CHAP.  I     The  Records  of  Gold  Washing. 

II.    History  and  Development  of  Placer  Mining  in  Cali- 
fornia. 

III.  General  Topography  and  Geology  of  California. 

IV.  The   Distribution   of  Gold  and  Deposits,  and    the 

Value  of  Different  Strata. 

V.  Amount  of  Workable  Gravel  Remaining  in  California. 

VI.  The  Different  Methods  of  Mining  Gold  Placers. 

VII.  1're  iminary  Investigations. 

VIII  Reservoirs  and  Dams 

IX.  Measurement  of  Flowing  Water. 

X.  Ditches  and  Flumes. 

XI.  Pipes  and  Nozzles. 

XII.  Various  Mechanical  Appliances. 

XIII.  Blasting  Gravel  Banks. 

XIV.  Tunnels  and  Sluices. 
XV.  Tailings  and  Dump. 

XVI  Washing  or  Hydraulicing. 

XVII.  Distribution  of  Gold  in  SSluices. 

XVIII.  Loss  of  Gold  and  Quicksilver. 

XIX.  Duty  of  the  Miner's  Inch. 

XX.  Statistics  of  the  Costs  of  Working,  and  the  Yield  of 

D.  VAN  HOST  RAND  COMPANY,  Publishers, 

23  Murray  &  27  Warren  Sts.,  New  York. 

*  Copies  sent  prepaid  on  receipt  of  price. 


Valuable  Books  for  me  Miner  ant  Metalinririst. 

THE  PROSPECTOR'S  HAND-BOOK, 

A  GUIDE  FOR  THE  PROSPECTOR  AND  TRAVELLER  IN 
SEARCH   OF  METAL-BEARING  OR  OTHER 

VALUABLE  MINERALS. 
By  J.  W.   ANDERSON,   M.  A.    [Camb.] 

Seventh  Edition,  Revised  and  Enlarged,  12mo,  Cloth,  $1.50. 


METALLURGY  OF  GOLD, 

A   PRACTICAL  TREATISE  ON 

The  Metallurgical  Treatment  of  Gold-Bearing  Ores 

INCLUDING  THE 

PROCESSES    OF   CONCENTRATION  AND  CHLORINATION, 
AND  THE  ASSAYING,  MELTING,  AND 

REFINING  OF  GOLD. 
By    M.    EISSLER. 

Fonrth  Edition,  Revised  and  Enlarged  to  700  Pages,  with  25  Addi- 
tional Plates,  and  Working  Drawings  and  Chapters  on 
Recent  Milling  Operations  in  the  Transvaal. 
8vo.,  Cloth,  Price  $5.00. 


THE  METALLURGY OFSILVER 

A   PRACTICAL  TREATISE  ON  THE  AMALGAMATION, 

ROASTING  AND  LIXIVATION  OF  SILVER  ORES, 

INCLUDING  THE  ASSAYING,  MELTING  AND 

REFINING  OF  SILVER  BULLION. 

By   M.   EISSLER. 
124  Illustrations.    Third  Edition,  Enlarged.     12mo.,  Cloth,   -  $4.00. 


The  Metallurgy  of  Argentiferous  Lead. 

A  PRACTICAL  TREATISE  ON  THE  SMELTING  OF  SILVER- 

LEAD  ORES  AND  THE  REFINING  OF  LEAD  BULLION. 

INCLUDING  REPORTS  ON  VARIOUS  SMELTING 

ESTABLISHMENTS  AND  DESCRIPTIONS  OF 

MODERN  SMELTING  FURNACES  AND 

PLANTS  IX  EUROPE  AND  AMERICA. 

By   M.   EISSLER. 
With  183  Illustrations.    8vo.,  Cloth,  $5.00. 


MACHINERY  FOR  METALLIFEROUS  MINES 

A  PRACTICAL  TREATISE  FOR  MINING  ENGINEERS, 

METALLURGISTS  AND  MANUFACTURERS. 

By  E.   H.   DAVIES. 

With  Upwards  of  300  Illustrations.     8vo.,  Cloth,         -  $5.00. 


A  TREATISE  ON 

METALLIFEROUS  MINERALS  AND  MINING 

By   D.   C.    DAVIES,   F.  G.  S. 

Fifth  Edition,  Revised,  with  Illustrations.     8vo.,  Cloth,  Price  $5.00. 


A  TREATISE  ON 

EARTHY  AND  OTHER  MINERALS  AND  MINING 

By   D.   C.    DAVIES. 

Third  Edition,  Revised  and  Enlarged,  with  Illustrations. 
8vo.,  Cloth.  Price        -        -        $5.00. 


MINERALOGY,  CRYSTALLOGRAPHY 
AND  BLOWPIPE  ANALYSIS, 

FROM  A   PRACTICAL  STANDPOINT 
By   ALFRED   J.    MOSES,    E.    M.,    Ph.    D., 

Adjunct  Professor    of    Mineralogy,  Columbia  College,   School    of 
Mines.  New  York  City, 

AND 

CHARLES   LATHROP    PARSONS,    B.    S., 

Professor  of  General  and   Analytical   Chemistry,  New  Hampshire 

College,  Dunham,  N.  H. 

A  Description  of  all  Common  or  useful  Minerals, 
and  Tests  necessary  for  their  Identification,  the 
Recognition  and  Measurement  of  their  Crys- 
tals, and  a  Concise  Statement  of  their 

Uses  in   the   Arts. 
8vo.,  Cloth,  336  Illustrations,  Price         -         -          $2.00. 


PRACTICAL  MINING. 

A    FIELD    MANUAL    FOR    MINING    ENGINEERS.        WITH 

HINTS  FOR  INVESTORS  IN  MINING  PROPERTIES. 

By   J.    G.    MURPHY. 

16mo.,  Morocco  Tiick^.  -         $1.00. 

A  PRACTICAL  TREATISE  ON 

HYDRAULIC  MINING  IN  CALIFORNIA, 

By   A.    J.    BOWIE. 
Fifth  Edition,  Small  Quarto,  Cloth.    Illustrated,       -       $5.00. 


MANUAL  OF  HYDRAULIC  MINING, 

For  the   Use  of  the  Practical  Miner. 

By   T.    F.   VAN   WAGENEN. 
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8vo,  CLOTH,       -      -      -      -        PRICE,  S3.OO. 


Cyanide  Process  for  the  Extraction  of  Gold 

AND 

ITS   PRACTICAL  APPLICATION   ON   THE 
WITSWATERSRAND  GOLD  FIELDS 
OF  SOUTH  AFRICA, 
By     M.     EISSLER, 

Mining  Engineer;  A.  I.  M.  E. ;  Member  of  the  Insti- 
tute of  Mining  and  Metallurgy,  Author 
of  "The  Metallurgy  of  Gold." 


CONTENTS. 

CHAPTER  I.— Erection  of  a  Cyanide  Plant;  CHAP.  II.— Extraction  by 
Cyanide;  CHAP.  III.— The  Sieniens-Halske  Process;  CHAP.  IV. 
Particulars  of  Operations  at  Various  Works;  CHAP.  V.— The 
Chemistry  of  the  Cyanide  Process.  Index. 


LIST  OF  ILLUSTRATION. 

1— Selection  of  Princess  Works.  2— Messrs.  Butters  &  Mein's 
Automatic  Distributor.  4,  5— Portrait  of  Mr.  Chas.  Butters.  6— 
Tailing  Wheel,  Vanner  Room  and  Cyanide  Vats  at  the  Jumpers  Mine . 
7— Staves  Cut  to  Circle.  8— Construction  of  Filter  Vats.  9— Stone 
Foundations  for  Filter  Vats.  10-Solution  Pipes.  11,  12— Butter's 
Discharge  Lid.  la— Zinc  Precipitation  Box.  14— The  Worcester- 
Cyanide  Plant.  15— The  Worcester  Cyanide  Plant.  16,  17,  18— 
Depositing  Box.  19 — General  View  of  the  Simmer  &  Jack  Cyanide 
Plant.  20— Simmer  &  Jack  Filter  Vats.  21,  22— Simmer  &  Jack 
Extraction  House.  23— Central  Works  of  the  Rand  Central  Ore 
Reduction  Company. 


A  Guide  to  the  Determination  of  Rocks: 

Being  an  Introduction  to  Lithology.      Translated 
from  the  French  by  G.    W.  Plympton,  Pro- 
fessor of  Physical  Science  at  Brook- 
lyn   Polytechnic    Institute. 
By     EDWARD     JANNETTAZ. 
12mo.,  Cloth,        -        -        $1.50. 


HAND-BOOK  OF  MINERALOGY; 

Determination   and  Description   of  Minerals 
Found  in  the   United  States. 

By   PROF.    J     C.    FOYE. 

(Van  Nostrand  Science  Series,  No.  86.)    Price        -       -       50  Cents. 


MANUAL  OF  BLOW-PIPE  ANALYSIS, 

QUALITATIVE  AND  QUANTITATIVE, 

With  a  complete  System  of  Determinative  Mineralogy.     With 
69  Wood  Cuts  and  one  Lithographic  Plate. 

By  H.  B.  CORNWALL. 
Fourth  Edition,  Revised.  8vo,  Cloth,  $2.50. 

TABLES 

Showing  Loss  of  Head  Due  to 
Friction  of  Water  in  Pipes. 

By   E.    B.   WESTON. 
12mo.,  Cloth,        -        -        -        $1.50. 


QUARTZ  OPERATOR'S  HAND-BOOK. 

By   P.    M.    RANDALL. 

New  Edition,  Revised  and  Enlarged,  Fully  Illustrated. 
12mo.,  Cloth,        -        -        $2  00. 


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